Brake shake with freshly machined rotors?
Nate Nagel
got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
had a pronounced steering shimmy under braking - the harder you brake,
the more the wheel shakes back and forth.
I finally took it in for its first service in my care today, and asked
them to balance and rotate the tires and also to turn the front rotors.
I ASSumed that this would take care of the issue (the tire balance was
because I was also having a shake at highway speed, not to address this
problem) but it did not - it's still doing it, and almost as badly as it
was before. The rotors show clear signs of having recently been
machined; there's obviously marks in the iron that are not
circumferential (I'm guessing they must have dressed it with a sanding
disc or similar while spinning on the brake lathe after turning) so it
doesn't appear to be a halfassed job on the part of the shop.
I'd suspected that the cause of this issue was because the car sat for
several months unused before I started driving it, so I just ASSumed
that the brake shake was due to rust buildup on the rotors (except of
course where the pads had sat, causing the rotors to wear unevenly when
the car was put back in service.) Of course, I suspect that also the
rotors are undersized for the weight of the car, but that's typical, and
if it were simply warping, wouldn't it take a while to reappear after
machining?
Any ideas as to why this could be?
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Scott Dorsey
>
>I'd suspected that the cause of this issue was because the car sat for
>several months unused before I started driving it, so I just ASSumed
>that the brake shake was due to rust buildup on the rotors (except of
>course where the pads had sat, causing the rotors to wear unevenly when
>the car was put back in service.) Of course, I suspect that also the
>rotors are undersized for the weight of the car, but that's typical, and
>if it were simply warping, wouldn't it take a while to reappear after
>machining?
>
>Any ideas as to why this could be?
Maybe you have a shimmy that is unrelated to the actual braking system.
Checked the tie rods? All the bushings? Get under there and start
tugging on stuff and seeing if you can feel any play in anything in the
front end.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Nate Nagel
Car has only 21K miles on it (about 4K of which are mine) it'd be pretty
pathetic if it had worn out suspension components already.
I didn't mention that it had a slow leak when I first got it and I'd
noticed that the steering wheel was slightly off center, so when I left
it to have the tire plugged I told them to check/correct the alignment.
One would think that that would involve doing all that you suggest.
jim
My guess would be a bad tire. Did they rotate them? It could also be a
sticking caliper, but then you would probably feel it in the brake pedal
also.
-jim
Anyolmouse
"Nate Nagel" <njn...@roosters.net> wrote in message
news:h1jd9...@news1.newsguy.com...
I have a 2000 Safari that has the same problem. It was okay for a short
time after a complete brake job. When it came back I called my mechanic
and he asked if I had had the tires rotated. Yep, just had that done. He
said he was running into a lot of this problem with different brands of
cars, vans, etc. He said that the rotors are warping when the wheels are
torqued during the rotation process. I pointed out that the tire shop I
use, uses a torque limiting air ratchet and that should not be a
problem. He agreed but said that was a common denominator to all of the
brake pulsating/ shimmy problems he has seen.
FWIW, If I intentionally brake heavy several times the pulsing problem
gets better and sometimes disappears. The rotors were still in specs
after being turned, but I think you may be right in thinking that they
are under engineered.
You didn't say how many miles is on the car, but the suspension is the
only thing I can think of that would cause the the highway shimmy. More
specific, the front shocks or struts, which ever it has.
I had a '93 S-10 that had bad bushings in the front A frame. It caused
the truck to veer to one side or the other under hard braking. There was
also a loud clunking sound when braking some times. It also exibited
some weird symptoms going down the highway. Sometimes, but not always,
the truck would get the shimmys after hitting a pot hole or going over a
bump. That all ws corrected when the bushins were replaced.
--
"We have no government armed with power capable of contending with human
passions unbridled by morality and religion. Avarice, ambition, revenge,
or gallantry, would break the strongest cords of our Constitution as a
whale goes through a net. Our Constitution was made only for a moral and
religious people. It is wholly inadequate to the government of any
other." --John Adams, October 11, 1798
Anyolmouse
Nate Nagel
Yes, the tires were supposedly both balanced and rotated, and I know the
tires are bad. They're Goodyear Integrity, the same crap tires that
were on my last car. Unfortunately there's not much I can do about that
unless I want to pay for new ones out of my pocket.
Nate Nagel
good point. maybe I will loosen/retorque lug nuts myself and see if
that helps.
Ashton Crusher
wrote:
There could be hard spots on the rotors. And perhaps while it was
sitting the area where the calipers were that did not rust is now
either harder or softer then the rest of it from that, although I
would not give that high odds. I had a impala back in the 70's that
did what you were describing and they only fix that worked was new
rotors.
HLS
"Anyolmouse" <Anyol...@invalid.invalid> wrote in message news:Uvb%l.13440
> use, uses a torque limiting air ratchet and that should not be a
> problem. He agreed but said that was a common denominator to all of the
> brake pulsating/ shimmy problems he has seen.
Those things dont always work they way they should. I have had two sets of
rotors warped
because of them.
HLS
>
> good point. maybe I will loosen/retorque lug nuts myself and see if that
> helps.
>
> nate
It's worth a try, but I doubt it will help..
As said before, tires are a possibility, bad machine work is another, and
tire/rotor
reinstallation (on some models) is a third.
I had some rotors cut once and when I remounted them on the GM product, you
could SEE
the wobble. The machinist didnt set up the lathe correctly.
If you dont still have the Coxco (?) link, let me know and I will find it
for you.
PeterD
wrote:
>Hi all,
>
>got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
>had a pronounced steering shimmy under braking - the harder you brake,
>the more the wheel shakes back and forth.
>
>I finally took it in for its first service in my care today, and asked
>them to balance and rotate the tires and also to turn the front rotors.
Just a suggestion: when you take a car in for warranty work, never
ever tell them 'how' to fix it. When you suggest a repair technique,
that is what the do, nothing else, because that is what you asked for.
Instead, give them the symptoms, make sure they can duplicate these
symptions and say: "Fix it, warranty". Heck, even if it is not
warranty, don't suggest how to repair a fault! People make this
mistake over and over--the shop must do what you suggest even if they
know it won't fix the problem, and they cannot fix anything else
because you asked for a specific action to be performed.
> I ASSumed that this
Never assume. Let the shop/mechanic find teh problem.
> would take care of the issue (the tire balance was
>because I was also having a shake at highway speed, not to address this
>problem) but it did not - it's still doing it, and almost as badly as it
>was before. The rotors show clear signs of having recently been
>machined; there's obviously marks in the iron that are not
>circumferential (I'm guessing they must have dressed it with a sanding
>disc or similar while spinning on the brake lathe after turning) so it
>doesn't appear to be a halfassed job on the part of the shop.
>
>I'd suspected that the cause of this issue was because the car sat for
>several months unused before I started driving it, so I just ASSumed
>that the brake shake was due to rust buildup on the rotors (except of
>course where the pads had sat, causing the rotors to wear unevenly when
>the car was put back in service.) Of course, I suspect that also the
>rotors are undersized for the weight of the car, but that's typical, and
>if it were simply warping, wouldn't it take a while to reappear after
>machining?
>
>Any ideas as to why this could be?
>
>nate
Well, first, a warranty repair should be done ASAP after the flaw is
noticed. Don't wait for other problems to appear. Second, don't assume
what is causing a problem. Now the dealer can say the did what you
asked, and will be reluctant to do more.
Possibly bad rotors, as you suspect. They could easily be warped, or
have excessive runout. Can't say until diagnostics are performed.
Ashton Crusher
wrote:
>Anyolmouse wrote:
I have done that on my explorer and it did help.
Vic Smith
wrote:
>Hi all,
>
>got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
>had a pronounced steering shimmy under braking - the harder you brake,
>the more the wheel shakes back and forth.
>
Steering Wheel Pull/Shimmy When Braking
PROBABLE CAUSE: REMEDY
Uneven braking force: Check for mechanical or hydraulic problem.
Inoperative brake: Check for seized caliper, fluid leak or
restriction, worn or contaminated lining.
Weak or broken spring: Replace spring.
Worn shocks or struts: Replace struts or shocks
Deteriorated suspension bushings (especially control
arm pivot): Replace bushings.
Loose wheel bearings: Adjust or replace bearings.
Excessive disc brake rotor run-out: Replace both front or rear brake
discs or rotors.
Improper front wheel alignment settings: Adjust alignment to factory
specifications.
(From http://www.thepartsbin.com/suspension-steering.html)
--Vic
Ashton Crusher
>On Sat, 20 Jun 2009 15:29:07 -0400, Nate Nagel <njn...@roosters.net>
>wrote:
>
>>Hi all,
>>
>>got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
>>had a pronounced steering shimmy under braking - the harder you brake,
>>the more the wheel shakes back and forth.
>>
>>I finally took it in for its first service in my care today, and asked
>>them to balance and rotate the tires and also to turn the front rotors.
>
>Just a suggestion: when you take a car in for warranty work, never
>ever tell them 'how' to fix it.
And when you do tell them you want something, ALWALYS get a price. I
learned that the hard way....I asked them to replace the brake
retainers figuring they couldn't be more then a couple bucks each.
When I got the bill I was about to call for the manager to figure out
why it was $70 higher then I expected till I saw what they price was
for the brake retainers......
Tegger
> Hi all,
>
> got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
> had a pronounced steering shimmy under braking - the harder you brake,
> the more the wheel shakes back and forth.
Of maybe some help:
<http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml#>
<http://www.brakeandfrontend.com/Article/39171/diagnostic_solutions_servicing_brake_rotors.aspx>
<http://www.brakeandfrontend.com/Article/38661/advanced_brake_diagnostic_tools.aspx>
>
> I finally took it in for its first service in my care today, and asked
> them to balance and rotate the tires and also to turn the front rotors.
> I ASSumed that this would take care of the issue (the tire balance was
> because I was also having a shake at highway speed, not to address this
> problem) but it did not - it's still doing it, and almost as badly as it
> was before.
Did anybody make certain the tires spun ABSOLUTELY true with NO
hop, wobble or snaking BEFORE balancing was attempted?
ANYthing but dead-true will result in unsatisfactory performance.
And those much-vaunted Hunter road-force machines tend to cover up
or disguise inept mounting, so they're not much of an answer.
I've had many years of tire replacements on several cars as personal experience
in this matter, many of those replacments being followed by highly
inconvenient and annoying multiple re-visits to the garage that did the work
in an attempt to get them to fix the vibration, which they rarely could.
I finally gave up and asked my mechanic if he could install tires for me.
he said sure. What a difference. So far, glass-smooth EVERY time.
Even though his "bedside manner" isn't that great, I worked up the nerve
to ask him why he was able to do this and nobody else appears to be able to.
He explained the problem in great detail, and showed me physical
evidence of why so many places have problems with comebacks due to
vibration, using my own tires (mounted by somebody else) as one example.
The upshot? Basically, inept technique. Mounting tires properly is not
difficult at all, but does require some very basic knowledge of some
very simple things. Problem is, most tire monkeys receive little training,
and their bosses understand little to begin with.
--
Tegger
Nate Nagel
> Nate Nagel <njn...@roosters.net> wrote in news:h1jd9...@news1.newsguy.com:
>
>> Hi all,
>>
>> got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
>> had a pronounced steering shimmy under braking - the harder you brake,
>> the more the wheel shakes back and forth.
>
>
>
> Of maybe some help:
> <http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml#>
> <http://www.brakeandfrontend.com/Article/39171/diagnostic_solutions_servicing_brake_rotors.aspx>
> <http://www.brakeandfrontend.com/Article/38661/advanced_brake_diagnostic_tools.aspx>
>
>
>
>> I finally took it in for its first service in my care today, and asked
>> them to balance and rotate the tires and also to turn the front rotors.
>> I ASSumed that this would take care of the issue (the tire balance was
>> because I was also having a shake at highway speed, not to address this
>> problem) but it did not - it's still doing it, and almost as badly as it
>> was before.
>
>
>
> Did anybody make certain the tires spun ABSOLUTELY true with NO
> hop, wobble or snaking BEFORE balancing was attempted?
I can't answer this question (see below)
>
> ANYthing but dead-true will result in unsatisfactory performance.
> And those much-vaunted Hunter road-force machines tend to cover up
> or disguise inept mounting, so they're not much of an answer.
>
> I've had many years of tire replacements on several cars as personal experience
> in this matter, many of those replacments being followed by highly
> inconvenient and annoying multiple re-visits to the garage that did the work
> in an attempt to get them to fix the vibration, which they rarely could.
>
> I finally gave up and asked my mechanic if he could install tires for me.
> he said sure. What a difference. So far, glass-smooth EVERY time.
> Even though his "bedside manner" isn't that great, I worked up the nerve
> to ask him why he was able to do this and nobody else appears to be able to.
> He explained the problem in great detail, and showed me physical
> evidence of why so many places have problems with comebacks due to
> vibration, using my own tires (mounted by somebody else) as one example.
>
> The upshot? Basically, inept technique. Mounting tires properly is not
> difficult at all, but does require some very basic knowledge of some
> very simple things. Problem is, most tire monkeys receive little training,
> and their bosses understand little to begin with.
You just described the exact problem that was driving me nuts on my 944
for literally years until I found a local Porsche club guy who had his
own tire machine.
However I have yet to report success because both my rim and tire
exhibited runout and I haven't had a chance to swap the tire (on a
straight rim) back on the car to see if it is acceptable or if I need
another new tire.
But back to the problem at hand, I am limited to two repair shops for
work on this car unless I want to pay for the work myself (fleet car) so
it may simply remain unresolved, much as it bothers me (I know it can't
be good for ball joints, tie rod ends, etc.) Or if I end up with a
windfall sometime soon, I may take it to a GOOD shop and just point and
say "fix."
Sharky
difference as far as the warping is concerned. The lathe will just follow
the warp in the rotor and cut it the same, only thinner. Sounds like you
need a new set of rotors. I would check the rear brakes to make sure they
are operating as well, usually warped rotors result from either too much
effort on the part of the front brakes trying to stop the car (excessive
heat), or a mechanic overtorquing the wheel nuts upon reinstallation and
unintentionally causing the warpage in the rotors.
How much pad lining is left on the front pads? Did they re-use the original
pads, or install new ones? When they re-installed the caliper sliding pins,
did they clean and then grease the pins and sliders so that the caliper
slides freely?
Just my 2 cents,
Sharky
HLS
"Sharky" <cl_8...@hotmail.com> wrote in message
news:acf%l.32875$PH1.11637@edtnps82...
> You can machine warped rotors all you like, but it will not make any
> difference as far as the warping is concerned. The lathe will just follow
> the warp in the rotor and cut it the same, only thinner.
Absolute caca.. If you do it right, you can definitely machine the rotors,
and
if you reinstall correctly this can last a long time.
I suspect you had some bad experiences, Sharky.
Nate Nagel
50-75% pad left, original pads, and no idea if they lubed it. If I'd
done it myself I'd have lubed it, but I don't feel like working on
company car myself. I did change the oil when I first got it because it
was due on time but not on mileage (so I couldn't get them to pay for
it) and I was so paranoid, even though I've never screwed up an oil
change in my life.
Ashton Crusher
wrote:
>You can machine warped rotors all you like, but it will not make any
>difference as far as the warping is concerned. The lathe will just follow
>the warp in the rotor and cut it the same, only thinner.
Really? So how do they make them in the first place!!! Do you think
they just come from the casting bed already machined?
Mike Marlow
"HLS" <nos...@nospam.nix> wrote in message
news:z9c%l.179$aX1...@nlpi067.nbdc.sbc.com...
It is very true that they don't always work as advertised. That said - it
is important to not that the precise torque that one would achieve with a
torque wrench is not necessary either. Yes - over torquing can warp a
rotor, but... and it's a bit butt, you have to overtorque a lot to incur
this problem. Allow wheels, or not - you have to go a long way to incur
this problem. Torque is often the first thing people speak of but it is
usually not the real culprit. Cheap rotors are a very common culprit.
Cheap pads are another. Switching to ceramics makes a huge difference in
heat dissipation, therefore the problems. So - it may be warpage, but that
warpage is more likely to be component related than it is to be torque
related.
--
-Mike-
mmarlo...@windstream.net
Mike Marlow
"PeterD" <pet...@hipson.net> wrote in message
news:h5kq351kt3j0keevn...@4ax.com...
> Just a suggestion: when you take a car in for warranty work, never
> ever tell them 'how' to fix it. When you suggest a repair technique,
> that is what the do, nothing else, because that is what you asked for.
> Instead, give them the symptoms, make sure they can duplicate these
> symptions and say: "Fix it, warranty". Heck, even if it is not
> warranty, don't suggest how to repair a fault! People make this
> mistake over and over--the shop must do what you suggest even if they
> know it won't fix the problem, and they cannot fix anything else
> because you asked for a specific action to be performed.
Not true at all. They are not obligated to fix as you suggest, and
generally don't.
>
> Never assume. Let the shop/mechanic find teh problem.
Bull. Many of us know exactly the path of troubleshooting, and the more
likely problems. Knowledge is worth acting on.
>
> Well, first, a warranty repair should be done ASAP after the flaw is
> noticed. Don't wait for other problems to appear. Second, don't assume
> what is causing a problem. Now the dealer can say the did what you
> asked, and will be reluctant to do more.
Bull again. The dealer will and is, obligated to take your input into
consideration, but to also apply their training and skills.
>
> Possibly bad rotors, as you suspect. They could easily be warped, or
> have excessive runout. Can't say until diagnostics are performed.
Agreed. And man, oh man, am I glad for that. I was beginning to feel like
I was doing nothing but disagree with you.
--
-Mike-
mmarlo...@windstream.net
Sharky
a tad better when reinstalled, you may as well purchase two new rotors that
you know will be straight. Those warped rotors are not only warped, but
have likely been subjected to extremely high temperatures and/or excessive
stress on the lug nut studs from overtorquing. Not only are they warped,
they more than likely have heat spots all over them. As far as I know, you
cannot remove heat spots by machining the rotor. No, I haven't had that
many bad experiences, but I can tell you for a fact, that it is much more
cost effective in the long run to just purchase two new rotors. Buy one set
of rotors the first time, as opposed to paying to machine an old set and
then having to replace them much sooner down the road than you had wanted
to, with a new set.
Another factor is whether you plan to keep the car long or short term. I
tend to keep my vehicles long term, thus my reasoning for my reply.
Sharky
HLS
> By the time you pay to machine two warped rotors, which are only going to
> be a tad better when reinstalled, you may as well purchase two new rotors
> that you know will be straight.
Horse stuff...You really dont seem to know what you are talking about at
all.
If the original rotors have enough meat left to allow them to be machined,
and IF
they are machined properly and installed properly, they will normally be
okay.
Buying a new rotor is likely to give you a good platform, but not
necessarily.
They should be surfaced, in most cases, to be sure the pads seat in well,
and they CAN be warped (directly from the factory in China).
Toyota MDT in MO
then fixing their mistakes and thievery, will do to your bedside manner.
--
Toyota MDT in MO
Toyota MDT in MO
> You can machine warped rotors all you like, but it will not make any
> difference as far as the warping is concerned. The lathe will just
> follow
> the warp in the rotor and cut it the same, only thinner.
Which "the lathe" are you referring to? Have you had bad experiences
with the Tyco or Fisher Price offerings?
> Sounds like you
> need a new set of rotors. I would check the rear brakes to make sure
> they
> are operating as well, usually warped rotors result from either too much
> effort on the part of the front brakes trying to stop the car (excessive
> heat), or a mechanic overtorquing the wheel nuts upon reinstallation and
> unintentionally causing the warpage in the rotors.
>
Perhaps he unevenly "torqued" (with a "torque stick") the wheels or
didn't cut the rotors properly, or was using one of the lathes you've
had bad experiences with.
> How much pad lining is left on the front pads? Did they re-use the
> original
> pads, or install new ones?
If the answer is 'more than 3 mm', what would you say to that?
> When they re-installed the caliper sliding pins,
> did they clean and then grease the pins and sliders so that the caliper
> slides freely?
>
Probably not; without confirmation, we can assume that this is the
average tech doing warranty work here...
PeterD
<mmarlo...@windstream.net> wrote:
>
>"PeterD" <pet...@hipson.net> wrote in message
>news:h5kq351kt3j0keevn...@4ax.com...
>
>> Just a suggestion: when you take a car in for warranty work, never
>> ever tell them 'how' to fix it. When you suggest a repair technique,
>> that is what the do, nothing else, because that is what you asked for.
>> Instead, give them the symptoms, make sure they can duplicate these
>> symptions and say: "Fix it, warranty". Heck, even if it is not
>> warranty, don't suggest how to repair a fault! People make this
>> mistake over and over--the shop must do what you suggest even if they
>> know it won't fix the problem, and they cannot fix anything else
>> because you asked for a specific action to be performed.
>
>Not true at all. They are not obligated to fix as you suggest, and
>generally don't.
>
Not sure where you are, but consumer protection laws in most states
govern this, and when a customer asks for a specific fix or action,
they are required to do it. I've never seen a shop that would do
something else, they risk the customer's rath and a complaint to the
state if they do so.
That would be something like going into a bakery and asking for a loaf
of white bread, being given a loaf of whole wheat (because it is
healther) and that substitution being OK.
>>
>> Never assume. Let the shop/mechanic find teh problem.
>
>Bull. Many of us know exactly the path of troubleshooting, and the more
>likely problems. Knowledge is worth acting on.
Clearly the OP didn't, or he would not have specified a repair that
was ineffective and probably unnecessary. I saw no indications of
technical skill, no indications of any diagnostic process other than
'assume', 'assumed' and probably a bit of guess and by gosh.
>
>>
>> Well, first, a warranty repair should be done ASAP after the flaw is
>> noticed. Don't wait for other problems to appear. Second, don't assume
>> what is causing a problem. Now the dealer can say the did what you
>> asked, and will be reluctant to do more.
>
>Bull again. The dealer will and is, obligated to take your input into
>consideration, but to also apply their training and skills.
Again, no, this is not the way things happen. At least in most states.
You ask for something specific, that is *exactly* what they must do,
or do nothing unless you say so. So often it is inpossible to
determine whether the customer's request is reasonable or going to
resolve any problem, so the shop will do what the customer
requests--provide that loaf of white bread.
>
>>
>> Possibly bad rotors, as you suspect. They could easily be warped, or
>> have excessive runout. Can't say until diagnostics are performed.
>
>Agreed. And man, oh man, am I glad for that. I was beginning to feel like
>I was doing nothing but disagree with you.
Oh, hell, you can disagree. I'm respected in my field, and know what
I'm saying (and when someone comes to me and asks for a specific
repair or process, I make it a point to impress on the customer that I
cannot ensure that the repair will do anything other than cost him/her
money.
The OP would have been much better off just taking it in and saying:
"Here is what happens, please fix it", instead of suggesting repair
methodologies.
PeterD
wrote:
>
>50-75% pad left, original pads, and no idea if they lubed it. If I'd
>done it myself I'd have lubed it, but I don't feel like working on
>company car myself. I did change the oil when I first got it because it
>was due on time but not on mileage (so I couldn't get them to pay for
>it) and I was so paranoid, even though I've never screwed up an oil
>change in my life.
>
>nate
Is this thing still under warranty? If not, why?
Tegger
news:%wi%l.248$OF1...@nlpi069.nbdc.sbc.com:
> Tegger wrote:
>>
>> The upshot? Basically, inept technique. Mounting tires properly is
>> not difficult at all, but does require some very basic knowledge of
>> some very simple things. Problem is, most tire monkeys receive little
>> training, and their bosses understand little to begin with.
>>
>>
>>
>>
>>
>>
> It's amazing what constantly being underbid by incompetent thieves,
> and then fixing their mistakes and thievery, will do to your bedside
> manner.
>
Price did not enter into it for me. One of the places that was inept was
the local Acura dealer ($110/hr shop rate!). I even made a point of telling
everybody I did not care what they charged me, so long as the tires ran
smooth the first time. Nobody ever charged me any more than their standard
fee.
The reason I was using tire shops instead of my guy was because the tire
shops were conveniently close. In some cases, they were within walking
distance of my work.
My guy is 60 miles away. He gives me a loaner car, but I still have to find
the time to get out there, then time to go back and get my car when it's
ready. I used to live much closer, but we moved away in 1994.
I stand by my final assertion: "Problem is, most tire monkeys receive
little training, and their bosses understand little to begin with."
Tire mounting appears to be the sort of job given to the lowest-paid and
least experienced person in the shop.
--
Tegger
twisted
>
> One of your tires is bad. Check for bumps or imperfections in the
> sidewalls.- Hide quoted text -
>
> - Show quoted text -
A bad tire will not make the brake pedal shake!
twisted
...nor will a bad tire make the steering wheel shake under braking!
HLS
> On Sat, 20 Jun 2009 22:10:55 -0400, "Mike Marlow"
> <mmarlo...@windstream.net> wrote:
>
>>
>>"PeterD" <pet...@hipson.net> wrote in message
>>news:h5kq351kt3j0keevn...@4ax.com...
>>
>>> Just a suggestion: when you take a car in for warranty work, never
>>> ever tell them 'how' to fix it.
One of the problems, I think, is that the client and the mechanic don't take
the time to even briefly discuss the problem and what is expected. That
could save a lot of hard feelings.
I have seen it too many times...clients dont know anything about mechanical
issues, and mechanics dont want to waste their time talking to the client.
HLS
This is the location of the previous Babcox site, and there is a lot of good
information if you will dig for it.
Sharky
rotor that has likely been pushed over its' limit more than once, and then
you take that rotor and make the surface even thinner than it was, how can
that possibly be any better than buying new? Nevermind the fact that the
metal properties of the rotor have already been effected from excessive
heat. And knowing that it probably cost you 2/3rds of buying new in the
first place. Personally, I don't believe in doing things half-assed, nor
do I have the extra time or desire to have to re-do the same job 6 months
down the road. As far as buying new rotors and them already being warped, I
don't buy no-name parts in the $20 or less bin. You can buy a medium to
high quality rotor and still pay under $75 each, in most cases. More than
likely it was made right here in NA and not overseas.
Listen, if I had a machine in my shop at my disposal, of course I would
resurface the old rotors, so long as they met the requirements to do so.
But in the middle of a brake job, with the front-end of my car in pieces, I
am not going to try and find a way to the closest shop with a lathe and then
turn around and pay anywhere from $20 to $50 per rotor to have them
machined. For one, not everyone has a second car in the driveway to be able
to do that. Secondly, you have no idea how that rotor is going to turn out.
Even an expert machinist may not be able to cut it perfectly. And if he
doesn't, that's the same as taking a lighter to the money you just spent on
that used rotor. No, I'd rather just pick up a pair of rotors while I'm
already at the parts store to get pads and whatever else I need. That way,
I have two new rotors sitting beside me when the brakes are ready to go back
together.
I'm talking about cost in the long run and life of the used rotor. It makes
much more sense to buy two new rotors as opposed to machining used/warped
rotors that will probably last under a year. The last time I had
rotors/drums machined, it cost me about $30-$40 per rotor/drum. For most
domestic vehicles I have owned in the last 10 years, add ~$25 or less per
unit and you have new, with warranty. What happens when that used rotor
fails a second time around, and you have no option of machining it? Don't
tell me you search all the junk yards for a used pair to resurface?
Sharky
HLS
Maybe you have had some bad luck. I certainly would support that some
rotors shouldn't be machined and should be replaced with new.
But not every occasion of warpage demands a new rotor.
Machining at the local shop here is $15 a rotor. New rotors cost varies a
lot.
A lot of mechanics just replace caliper and rotor, because they believe the
cost
is equal or less than doing a good renovation job (and it MIGHT be), because
they dont want comebacks of the type you describe, and because the customer
pretty much has to pay whatever the case.
Ed Pawlowski
>>> ever tell them 'how' to fix it. When you suggest a repair technique,
>>> that is what the do, nothing else, because that is what you asked for.
>>> Instead, give them the symptoms, make sure they can duplicate these
>>> symptions and say: "Fix it, warranty".
>>
>>generally don't.
>>
>
> Not sure where you are, but consumer protection laws in most states
> govern this, and when a customer asks for a specific fix or action,
> they are required to do it. I've never seen a shop that would do
> something else, they risk the customer's rath and a complaint to the
> state if they do so.
>
> That would be something like going into a bakery and asking for a loaf
> of white bread, being given a loaf of whole wheat (because it is
> healther) and that substitution being OK.
If you are paying for the work they should do what you ask. Warranty work
though, is a different matter. The car maker is paying for the work and he
will want it fixed according to the diagnosis of his trained mechanic, not
some rube off the street that has not looked under the hood since 1962.
That said, after 3 visits to my Buick dealer for an AC repair, I told them
what to do. They stood firm at first and said "evaporator coils never
leak". Then they took ten minutes to check it. Then they ordered the coil.
Smart shops will listen to the customer and possibly even start the repair,
then show the customer what the real problem is and how they can fix it.
Canuck57
"Nate Nagel" <njn...@roosters.net> wrote in message
news:h1jgn...@news7.newsguy.com...
> jim wrote:
>>
>> Nate Nagel wrote:
>>> Hi all,
>>>
>>> got a bit of a puzzlement. Ever since I've had it, my '08 Impala has
>>> had a pronounced steering shimmy under braking - the harder you brake,
>>> the more the wheel shakes back and forth.
>>>
>>> them to balance and rotate the tires and also to turn the front rotors.
>>> I ASSumed that this would take care of the issue (the tire balance was
>>> because I was also having a shake at highway speed, not to address this
>>> problem) but it did not - it's still doing it, and almost as badly as it
>>> machined; there's obviously marks in the iron that are not
>>> circumferential (I'm guessing they must have dressed it with a sanding
>>> disc or similar while spinning on the brake lathe after turning) so it
>>> doesn't appear to be a halfassed job on the part of the shop.
>>>
>>> I'd suspected that the cause of this issue was because the car sat for
>>> several months unused before I started driving it, so I just ASSumed
>>> that the brake shake was due to rust buildup on the rotors (except of
>>> course where the pads had sat, causing the rotors to wear unevenly when
>>> the car was put back in service.) Of course, I suspect that also the
>>> rotors are undersized for the weight of the car, but that's typical, and
>>> if it were simply warping, wouldn't it take a while to reappear after
>>> machining?
>>>
>>> Any ideas as to why this could be?
>>
>> sticking caliper, but then you would probably feel it in the brake pedal
>> also.
>>
>
> Yes, the tires were supposedly both balanced and rotated, and I know the
> tires are bad. They're Goodyear Integrity, the same crap tires that were
> on my last car. Unfortunately there's not much I can do about that unless
> I want to pay for new ones out of my pocket.
>
> nate
But don't write off tires.
Twice now I have been hjacked around because they were in warranty and they
didn't want to exchange them.
One set was OEM factory on a new vehicle. Just lived with the nuances until
we replaced them at 55,000 mi. or so. The new tires of a differnet brand
solved a lot of problems in stearing, braking and steering. I let the
dealer convince me it was "normal". Wish I hadn't, because I became quite
irrate after changing the tires to find out it was tires all along.
Another time we had similar issues but also could not get a good alignment.
It was pretty bad, 4 allignments, 2 brake checks later I said if you do not
warranty them, I will buy a different brand elsewhere and have these sent to
the safety government people. I had a new set on ASAP and the problems went
away.
All too often it is the tires and they try to putz with the alignment or
something else to compensate.
N8N
I didn't specify a repair, I described the symptoms, and said
something like "it feels like the rotors may be warped." I agree with
your point, don't diagnose something for the wrench unless you are
100% sure that you are right.
>
> >> Well, first, a warranty repair should be done ASAP after the flaw is
> >> noticed. Don't wait for other problems to appear. Second, don't assume
> >> what is causing a problem. Now the dealer can say the did what you
> >> asked, and will be reluctant to do more.
>
> >Bull again. The dealer will and is, obligated to take your input into
> >consideration, but to also apply their training and skills.
>
> Again, no, this is not the way things happen. At least in most states.
> You ask for something specific, that is *exactly* what they must do,
> or do nothing unless you say so. So often it is inpossible to
> determine whether the customer's request is reasonable or going to
> resolve any problem, so the shop will do what the customer
> requests--provide that loaf of white bread.
>
>
>
> >> Possibly bad rotors, as you suspect. They could easily be warped, or
> >> have excessive runout. Can't say until diagnostics are performed.
>
> >Agreed. And man, oh man, am I glad for that. I was beginning to feel like
> >I was doing nothing but disagree with you.
>
> Oh, hell, you can disagree. I'm respected in my field, and know what
> I'm saying (and when someone comes to me and asks for a specific
> repair or process, I make it a point to impress on the customer that I
> cannot ensure that the repair will do anything other than cost him/her
> money.
>
> The OP would have been much better off just taking it in and saying:
> "Here is what happens, please fix it", instead of suggesting repair
> methodologies.
And that's what I believe happened, except for the fact that the
problem was not fixed. However, a visual inspection shows that they
did in fact do what in my mind should have most likely rectified the
problem, at least temporarily, but it did not.
If it's tires, I'm just going to have to live with it... like I said
this is a company car and while I am trying to take good care of this
one a) I can't afford for it to be in a shop for a lengthy period of
time and b) things like new tires, brakes, etc. for non-worn-out
components would come out of my own pocket because there's no way in
hell the fleet people would pay for it.
in fact, I'm surprised that they've paid for the alignment, wheel
balance, tire rotation, and now this latest messing with the brakes,
which I've all requested since I got the car 4K miles ago. However
the car drives so much better now that all that's been done that I
feel pretty confident in saying that it's better to have done it early
than not. (and why should a car need alignment at 14K-ish miles, when
I first got it? I don't know, but it did.)
nate
Toyota MDT in MO
doesn't win any friendship awards. Most of the time truly good techs
work for less $ overall than the competing thieves, add to that - guess
who undoes the previous failures, butchery, and needless parts
shotgunning performed by said thieves? Then guess who the average
customer thinks is the better mechanic? Naturally, the one armed with
more BS advertising, flowery ass smoke, and (needless) parts sales. The
real shop who charges 1 - 3 hours labor and $10 in wiring supplies (and
actually spends that much time finding/fixing the difficult problem)
can't even get this type of customer to come back for PM or "normal"
repairs where a comfortable living can be made.
N8N
meh, if I can find a crusty old guy who works in a two-bay garage with
a greasy pit in the floor, but he fixes my crap RIGHT he can give me
all the attitude he wants.
The best alignment shop I've ever been to did in fact give you your
"alignment report" scribbled in pencil on whatever paper happened to
be laying around and the measurements were all in inches. Alignment
rack? they had steel ramps and big ass trammels instead. But my cars
never drove better...
nate
M.M.
the same stuff, even got new tires (she needed them anyway). I finally
said to hell with it & replaced the front discs & pads...problem solved.
HLS
"N8N" <njn...@hotmail.com> wrote in message news:8cea8f12-19ff-4dbf-81aa-
And that's what I believe happened, except for the fact that the
problem was not fixed. However, a visual inspection shows that they
did in fact do what in my mind should have most likely rectified the
problem, at least temporarily, but it did not.
*******************
Read the Babcox site. Just machining the rotors is not always the
total cure, especially if they are machined off the car.
And if the technician were pressed (as dealerships sometime do),
he might have rushed through the work.
If a person really wants to know if the rotors are still deformed,
they can be measured by dial indicator for run-out, or by a caliper
for thickness variation.
Had this happen to a friend just a week or so ago. The mechanic
turned the rotors but didnt do a good job. Most of the shudder
is gone, but not all of it. A real pisser.
If the technician installs new rotors, but doesnt check them for
mating trueness, you can still have a problem. Again, machining
them on the car can give relief from this.
Toyota MDT in MO
> On Sat, 20 Jun 2009 22:10:55 -0400, "Mike Marlow"
> <mmarlo...@windstream.net> wrote:
>
>
>> "PeterD" <pet...@hipson.net> wrote in message
>> news:h5kq351kt3j0keevn...@4ax.com...
>>
>>
>>> Just a suggestion: when you take a car in for warranty work, never
>>> ever tell them 'how' to fix it. When you suggest a repair technique,
>>> that is what the do, nothing else, because that is what you asked for.
>>> Instead, give them the symptoms, make sure they can duplicate these
>>> symptions and say: "Fix it, warranty". Heck, even if it is not
>>> warranty, don't suggest how to repair a fault! People make this
>>> mistake over and over--the shop must do what you suggest even if they
>>> know it won't fix the problem, and they cannot fix anything else
>>> because you asked for a specific action to be performed.
>>>
>> Not true at all. They are not obligated to fix as you suggest, and
>> generally don't.
>>
>>
>
> Not sure where you are, but consumer protection laws in most states
> govern this, and when a customer asks for a specific fix or action,
> they are required to do it. I've never seen a shop that would do
> something else, they risk the customer's rath and a complaint to the
> state if they do so.
>
> That would be something like going into a bakery and asking for a loaf
> of white bread, being given a loaf of whole wheat (because it is
> healther) and that substitution being OK.
>
>
>
It would be much more like bringing in your just-purchased loaf of bread
(still under warranty) and complaining that it hadn't risen enough, then
telling the bakery's service advisor "too low yeast content during
manufacture is the cause, please add more yeast". The fact is that the
loaf had enough yeast in it but it wasn't baked fully. The proper fix
would be to bake it fully, but an incompetent service advisor would heed
the customer's request and end up with wasted money and a non-repair.
Yes, this analogy is technically ludicrous, just trying to make a point.
>>> Never assume. Let the shop/mechanic find teh problem.
>>>
>> Bull. Many of us know exactly the path of troubleshooting, and the more
>> likely problems. Knowledge is worth acting on.
>>
>
> Clearly the OP didn't, or he would not have specified a repair that
> was ineffective and probably unnecessary. I saw no indications of
> technical skill, no indications of any diagnostic process other than
> 'assume', 'assumed' and probably a bit of guess and by gosh.
>
>
Agreed. The problem is that customers don't necessarily know *not* to
suggest a repair, whether we're talking about warranty or pay services.
The service advisor should know better, however, and not write up "turn
front rotors", rather he should write "complaint: vibration when braking
at 45+ mph that can be felt in the steering wheel" or similar (don't
remember Nate's actual complaint to the letter).
HLS
"Toyota MDT in MO" <toyota...@yahoo.com> wrote in message news:7Os%l.208
> I was merely explaining why the guy you go to (because he's good) doesn't
> win any friendship awards. Most of the time truly good techs work for
> less $ overall than the competing thieves, add to that - guess who undoes
> the previous failures, butchery, and needless parts shotgunning performed
> by said thieves? Then guess who the average customer thinks is the better
> mechanic? Naturally, the one armed with more BS advertising, flowery ass
> smoke, and (needless) parts sales. The real shop who charges 1 - 3 hours
> labor and $10 in wiring supplies (and actually spends that much time
> finding/fixing the difficult problem) can't even get this type of customer
> to come back for PM or "normal" repairs where a comfortable living can be
> made.
>
> --
> Toyota MDT in MO
Agree totally.
The guy who does a good job and checks his work may, unfortunately make
less money than the guy trying to beat the flat rate, putting on unnecessary
parts,
and doing that shoddily.
That is why it is important to find a good mechanic and support him or her.
If
you can trust him, and he knows his stuff, he is worth the money.
Vic Smith
That's always worked for me, though it only happened on one car.
And the new rotors were only 20 bucks each.
When the rotors are expensive, you might want to look for other
solutions first.
--Vic
Toyota MDT in MO
>
>
I'm a crusty young guy that generally fits that description, but I
imagine the vehicle freight charges would negate any savings :-) Also,
find a crusty guy that doesn't get his crust on your car. Greasy isn't
good on fabric or fenders. A 100% successful repair is one that
addressed only the actual failed part(s), was done in a timely and
convenient manner to the customer, and the car was returned at least as
clean as it was brought in. Being nice to the customer really hinges on
whether the customer was nice to begin with and isn't always included in
the cost :-)
N8N
> On Sat, 20 Jun 2009 20:56:19 -0400, Nate Nagel <njna...@roosters.net>
theoretically, but because it is a fleet car, for anything I take it
to one of two "approved" shops. If they say it has to go to the
dealer, *then* I take it to the dealer.
I really wanted to get my local wrench (near my house) with the
program so I could just drop it off there for maintenance/repair, but
when I tried to get them on board I inadvertantly caused all sorts of
kerfuffle and pissed off my boss, so I won't do that again. There's
some things that are worth making a big deal over, and there's times
you just grin and say "why yes, of course, I'll come in on Saturday
just so I can get my car serviced at the approved shop." Not that I'm
bitter or anything. Well, OK, I am, but aside from little PITA stuff
like this, I'm legitimately happy to still have a good job these
days. The pay's OK and even if it's a PITA to deal with, having a car
with gas and maintenance paid for is quite nice - certainly if I were
providing my own transportation my old 944 wouldn't cut it, not
without a major overhaul first, not with the amount and type (mostly
city, with interspersed blasts of high-speed freeway) driving that I
have to do. Even if my workload is temporarily doubled because
another employee decided that this wasn't the right place for her.
Yes, I am checking Usenet from my desk at work, while waiting for
files to download. *sigh* I have no life... (must remember to call
Dad later)
nate
HLS
> Hi all,
Here is another link for you, Nate:
http://www.brakeandfrontend.com/Article/46342/rotor_runout_check_list.aspx
Ashton Crusher
There's an entire shop management approach to maximizing profit that
says (I may have the percents wrong) every $100 in labor should be
matched by $200 in parts largely because the markup on parts is about
twice the markup on labor. These shops don't really want to do work
that is mainly labor. Try and find a place that will replace a rear
main seal.....much easier to find a place that will do a complete
rebuild.
Ashton Crusher
>
>"Sharky" <cl_8...@hotmail.com> wrote in message
>news:0Gg%l.32889$PH1.25975@edtnps82...
>> By the time you pay to machine two warped rotors, which are only going to
>> be a tad better when reinstalled, you may as well purchase two new rotors
>> that you know will be straight.
>
>
>Horse stuff...You really dont seem to know what you are talking about at
>all.
>
>If the original rotors have enough meat left to allow them to be machined,
>and IF
>they are machined properly and installed properly, they will normally be
>okay.
>
>Buying a new rotor is likely to give you a good platform, but not
>necessarily.
>They should be surfaced, in most cases, to be sure the pads seat in well,
>and they CAN be warped (directly from the factory in China).
>
>
>
no one who is up to date recommends resurfacing new rotors. When you
get a set of heads do you send them out to be milled???
HLS
"Ashton Crusher" <de...@moore.net> wrote in message
news:v11t35lsbqn7oidlu...@4ax.com...
Nope. By surfacing, I do not mean machining. Perhaps that is the issue.
Tegger
> Being nice to the customer
> really hinges on whether the customer was nice to begin with and isn't
> always included in the cost :-)
>
I always thought I was being a pretty decent customer to my guy. Maybe I'm
wrong.
--
Tegger
Nate Nagel
if I were going to "build it to last forever" I definitely would. And
ported, gasket matched, etc.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
Mike Marlow
> On Sat, 20 Jun 2009 22:10:55 -0400, "Mike Marlow"
> <mmarlo...@windstream.net> wrote:
>
>>
>>"PeterD" <pet...@hipson.net> wrote in message
>>news:h5kq351kt3j0keevn...@4ax.com...
>>
>>> Just a suggestion: when you take a car in for warranty work, never
>>> ever tell them 'how' to fix it. When you suggest a repair technique,
>>> that is what the do, nothing else, because that is what you asked for.
>>> Instead, give them the symptoms, make sure they can duplicate these
>>> symptions and say: "Fix it, warranty". Heck, even if it is not
>>> warranty, don't suggest how to repair a fault! People make this
>>> mistake over and over--the shop must do what you suggest even if they
>>> know it won't fix the problem, and they cannot fix anything else
>>> because you asked for a specific action to be performed.
>>
>>Not true at all. They are not obligated to fix as you suggest, and
>>generally don't.
>>
>
> Not sure where you are, but consumer protection laws in most states
> govern this, and when a customer asks for a specific fix or action,
> they are required to do it. I've never seen a shop that would do
> something else, they risk the customer's rath and a complaint to the
> state if they do so.
>
> That would be something like going into a bakery and asking for a loaf
> of white bread, being given a loaf of whole wheat (because it is
> healther) and that substitution being OK.
There is a difference. If you go in and say you want something done, that
is one thing. If you go in offering your suggestions or advice on how to
diagnose or repair a problem, that's an entirely different matter.
>
>
>>>
>>> Never assume. Let the shop/mechanic find teh problem.
>>
>>Bull. Many of us know exactly the path of troubleshooting, and the more
>>likely problems. Knowledge is worth acting on.
>
> Clearly the OP didn't, or he would not have specified a repair that
> was ineffective and probably unnecessary. I saw no indications of
> technical skill, no indications of any diagnostic process other than
> 'assume', 'assumed' and probably a bit of guess and by gosh.
>
Agreed. I should have stated my response better. In the case of the OP, I
agree with you. In the case of more knowledgable people, not so much.
>>
>>>
>>> Well, first, a warranty repair should be done ASAP after the flaw is
>>> noticed. Don't wait for other problems to appear. Second, don't assume
>>> what is causing a problem. Now the dealer can say the did what you
>>> asked, and will be reluctant to do more.
>>
>>Bull again. The dealer will and is, obligated to take your input into
>>consideration, but to also apply their training and skills.
>
> Again, no, this is not the way things happen. At least in most states.
> You ask for something specific, that is *exactly* what they must do,
> or do nothing unless you say so. So often it is inpossible to
> determine whether the customer's request is reasonable or going to
> resolve any problem, so the shop will do what the customer
> requests--provide that loaf of white bread.
>
Again - I think we're talking two different things.
--
-Mike-
mmarlo...@windstream.net
Toyota MDT in MO
a good customer. I was simply trying to explain why certain service
providers act the way they do in this business. The 'everyone's buddy'
'yes man' BSer personality is rarely one who does his job honestly and
competently in my experience.
jim
N8N wrote:
> >
>
> I didn't specify a repair, I described the symptoms, and said
> something like "it feels like the rotors may be warped." I agree with
> your point, don't diagnose something for the wrench unless you are
> 100% sure that you are right.
I think there may be something you are overlooking here. You described a
vibration in the steering wheel that got worse the harder you brake. So that is
all we (us readers) know.
The question is to what extent is this affecting your ability to make a panic
stop if you are cruising down the highway at 70 mph? If the guy ahead of you has
to slam on his brakes are you going to slam into his rear because his brakes are
a lot better than yours?
I ask this because it doesn't sound like they even test drove the car after
doing the work. It doesn't sound like they are taking this very seriously.
-jim
Nate Nagel
the brakes work fine, the tires suck though. that'll be what keeps me
from stopping as fast as I like if it comes to that. I just worry about
prematurely worn out steering parts, esp. since a common issue with this
chassis is rattly steering shaft couplers.
Ashton Crusher
If that's what you mean then sure, they should have the proper surface
finish on them. All the replacement rotors I've purchased have
already been given a proper non-directional finish by whoever made
them.
One thing a lot of people don't do that the repair manuals say is a
MUST is to wash the new rotors (or old freshly machined ones) with
soap and water. Supposedly that's the only way to get the fine metal
dust from the machining/surfacing operation out of the pores. If you
don't get that metal dust out then you may develop some sort of
non-uniformity in the surface soon after they go in service.
E. Meyer
<njn...@roosters.net> wrote:
My '00 Acura developed similar symptoms to what you describe while it was
still relatively new & at approximately the same mileage. The problem
turned out to be a defective upper ball joint. You may be on the right
track looking at suspension & steering components.
labatyd
"Mike Marlow" <mmarlo...@windstream.net> wrote in message
news:88263$4a3d9535$452897e0$82...@ALLTEL.NET...
>
> "HLS" <nos...@nospam.nix> wrote in message
> news:z9c%l.179$aX1...@nlpi067.nbdc.sbc.com...
>>
>> "Anyolmouse" <Anyol...@invalid.invalid> wrote in message
>> news:Uvb%l.13440 I pointed out that the tire shop I
>>> use, uses a torque limiting air ratchet and that should not be a
>>> problem. He agreed but said that was a common denominator to all of the
>>> brake pulsating/ shimmy problems he has seen.
>>
>> Those things dont always work they way they should. I have had two sets
>> of rotors warped
>> because of them.
>
> It is very true that they don't always work as advertised. That said - it
> is important to not that the precise torque that one would achieve with a
> torque wrench is not necessary either. Yes - over torquing can warp a
> rotor, but... and it's a bit butt, you have to overtorque a lot to incur
Torquing wheel nuts? How? Not from my experience. I've worked on quite a few
different vehicles over the years, used both impact and wrench. Not seen a
warpped rotor yet. Have had a few rotors pulsing but it always was
improperly machined rotors. Use a micrometer and check the thickness around
the diameter. Improper torque on wheel nuts will cost you a stud sometimes
though .
> this problem. Allow wheels, or not - you have to go a long way to incur
> this problem. Torque is often the first thing people speak of but it is
> usually not the real culprit. Cheap rotors are a very common culprit.
> Cheap pads are another. Switching to ceramics makes a huge difference in
> heat dissipation, therefore the problems. So - it may be warpage, but
> that warpage is more likely to be component related than it is to be
> torque related.
>
> --
>
> -Mike-
> mmarlo...@windstream.net
>
HLS
> MUST is to wash the new rotors (or old freshly machined ones) with
> soap and water. Supposedly that's the only way to get the fine metal
> dust from the machining/surfacing operation out of the pores. If you
> don't get that metal dust out then you may develop some sort of
> non-uniformity in the surface soon after they go in service.
I also think they should be washed. Soap and water would be fine,
or methylalcohol as in spray brake cleaners. I suspect that most
manufacturers apply some sort of filming corrosion inhitor to reduce
the rusting of shelf stock, and if so that should probably be removed.
HLS
"labatyd" <fa...@fake.net> wrote in message
>
> Torquing wheel nuts? How? Not from my experience. I've worked on quite a
> few different vehicles over the years, used both impact and wrench. Not
> seen a warpped rotor yet. Have had a few rotors pulsing but it always was
> improperly machined rotors. Use a micrometer and check the thickness
> around the diameter. Improper torque on wheel nuts will cost you a stud
> sometimes though .
It happens, I assure you, and have seen, and been, a victim of it. None of
the
local tire shops here even have a torque wrench. When I have to use them,
I carry mine along and torque the studs myself.
labatyd
"HLS" <nos...@nospam.nix> wrote in message
What kind of vehicle? Never seen it happen. I'd like to know how. I've seen
wheels with stud broken off. No problem. Now that's difference in torque.
labatyd
> You can machine warped rotors all you like, but it will not make any
> difference as far as the warping is concerned. The lathe will just follow
> the warp in the rotor and cut it the same, only thinner. Sounds like you
What?
> need a new set of rotors. I would check the rear brakes to make sure they
> are operating as well, usually warped rotors result from either too much
> effort on the part of the front brakes trying to stop the car (excessive
> heat), or a mechanic overtorquing the wheel nuts upon reinstallation and
> unintentionally causing the warpage in the rotors.
>
> How much pad lining is left on the front pads? Did they re-use the
> original
> pads, or install new ones? When they re-installed the caliper sliding
> pins,
> did they clean and then grease the pins and sliders so that the caliper
> slides freely?
>
> Just my 2 cents,
> Sharky
>
HLS
> seen wheels with stud broken off. No problem. Now that's difference in
> torque.
Ive seen it happen on lots of different types of vehicles. To name a few I
have
seen recently, Chevrolet truck, Chevrolet Impala, Toyota SUV, Dodge full
size van, etc etc.
None of these cars had any judder until locals fitted new tires or rotated
tires, and hammered on the lug nuts with an impact wrench. The judder
came on days to a few weeks after the work, and were cured by
machining the wobble out of them. I think heating of the discs which
are unevenly torqued down induces the distortion.
Whatever happens it is real, and it is avoidable.
labatyd
"HLS" <nos...@nospam.nix> wrote in message
I'm going to call you on that. Take a look at your rotor and hub. That hub
is SOLID. It has to be since it houses the bearings. Now the hub goes over
top followed by the wheel. Against a machined surface of the hub. Even with
two opposing bolts the rotor has to run true to the hub. How can it possibly
warp a rotor?
I'll keep doing all my own tire repairs and machining rotors. I've never
bothered with a torque wrench. My impact would never break a stud and I have
a pretty good idea what torque I'm getting if I do them by hand. I just
finished correcting a poorly machined rotor on my dad's car that was done by
a local shop. It was out by several thousands on the diameter. I have my own
lathe. Set it up with dial gauge on inside and machined the other to match.
Back on the Lumina, test drive and vibration gone.
The reason I understand that shops use a torque wrench is they don't want a
broken stud and it removes the guess work out. Any jockey can do the job
then and the shop isn't libel
Mike Marlow
"HLS" <nos...@nospam.nix> wrote in message
Here's my problem with that... it seems to be very anecdotal. I have seen
the same kind of problems on properly torqued wheels. My experience with
tire shops is very different from yours, though I do not question yours.
Mine is that they all use torque wrenches these days, and it has been years
since I saw a tech hammer a lug nut on with an impact.
My experiences are that rotors can be of low quality today - especially the
budget rotors, and it does not take any amount of heat to warp them.
Torqued lug nuts or not, they warp. I've also convinced myself that the
cheap pads add to heat in the rotor and that ceramics do a much better job
of dissipating that heat, thus reducing warping. I've used both
semi-metallic and ceramics on the same model of rotor, and found a distinct
difference between rotor anomalies with ceramics.
Contrary to that, I have also gone the route of meticulously torquing lugs,
to find no notable difference between torqued lug nuts and those that
weren't torqued.
--
-Mike-
mmarlo...@windstream.net
Vic Smith
There are internal stresses in rotors, and rotors themselves are of
different designs. The ones I've seen are hollow between the sides
for cooling/weight purposes. I can imagine that uneven stress on the
center can affect the outlying metal.
Too many people report bad torquing causes rotor distortion for me not
to believe it happens.
Like you I don't bother torquing when I change tires. Never have.
And the only time I had a warped rotor was right after I ran hot
brakes through a deep puddle.
I think some rotors aren't affected by lugnut torquing, and others
are.
Best not to find out which are which..
But I'll probably continue to roll the dice if the rotors are cheap.
--Vic
Mike Marlow
>
> The reason I understand that shops use a torque wrench is they don't want
> a broken stud and it removes the guess work out. Any jockey can do the job
> then and the shop isn't libel
>
The "requirement" for a torque wrench came along with the popularity of
alloy wheels. Rattling lug nuts on with an impact was considered to be
unhealthy for the alloy wheel. I've heard of cases of broken wheels, but
I've never seen one. I believe it might be much easier to create an oblong
hole in an alloy wheel than to break the wheel.
--
-Mike-
mmarlo...@windstream.net
labatyd
"Vic Smith" <thismaila...@comcast.net> wrote in message
news:nbuu3516fjnk0dllk...@4ax.com...
Yes and heat I will believe. It could drive the rotor to wobble enough that
the pads can't follow. But that would take a fair amount of heat to warp a
hunk of steel that heavy.
> I can imagine that uneven stress on the
> center can affect the outlying metal.
> Too many people report bad torquing causes rotor distortion for me not
> to believe it happens.
Baloney. I'd like to know how many wheels I've done over the years. I'm not
running a shop by any means but I've done a lot of work on vehicles and
machinery. I'll argue to the cows come home on this one. Heat sure, but
that's an entirely different matter.
> Like you I don't bother torquing when I change tires. Never have.
> And the only time I had a warped rotor was right after I ran hot
> brakes through a deep puddle.
> I think some rotors aren't affected by lugnut torquing, and others
> are.
> Best not to find out which are which..
> But I'll probably continue to roll the dice if the rotors are cheap.
They can believe it they wish. Old wives tale. I don't. Suspect it's any
easy way to convince people to replace with new. Anyone without real
experience with the tools can't argue. And the shop is clear. And that's the
most important part for a shop. You can't offend a customer with new parts.
>
> --Vic
labatyd
Ah ok. I'll buy that. I don't feel it's absolutely necessary but no harm in
taking a few extra minutes. I've heard bikers say they won't touch their
alloy rims personally for fear of damaging the metal which could lead to
fracture later on. Seems a bit of a streatch but I'm no biker and losing 50%
of your rubber at highway speed doesn't have a lot of appeal to me.
>
> --
>
> -Mike-
> mmarlo...@windstream.net
>
Vic Smith
It's more fun to argue about brake system flushes and how brake fluid
is constantly sucking up water until your MC starts overflowing.
--Vic
labatyd
lol
>
> --Vic
>
HLS
You can do what you want. I am telling you what I have found, and you can
take it or leave it. No hard feelings.
HLS
Rotors WERE beefier a few years ago, no doubt. I agree my observations
are anecdotal, but they have added up to some pretty firm evidence (not
proof, but evidence).
One of the Dodge van I personally experienced, a national tire chain
installed
new tires for me and in about a month the judder was there. Nothing before
that. DT had used the torque stix.
I pulled the rotors, had them machined true, and reinstalled them along with
new pads. Ran for two years that way with no problem whatsoever. Then
back to the same tire chain and -guess what - within a few weeks the
pulsation
and judder was back. (Cause and effect thinking starts here.)
After than, I adopted the torque wrench only policy and have had no more
problems.
I live in a small town. In a larger town, people have seen a torque wrench.
Here, they dont have them at all in the tire shops, etc. And the warpage
goes on. We had another car, a Buick, that suffered the same problems
after new tires were mounted, whereas it had none before....it is was NOT
a tire problem.
I have a long list of them. For me, it doesnt take but a few seconds longer
to torque the studs, star pattern.
Anyone who wants to ram them on with an impact wrench, go ahead.
(I have an impact wrench and use it for some front end work but not
for tires. I am not that lazy.) I am convinced it is not to my best
interest.
the fly
<theni...@yahoo.com> wrote:
>On Jun 21, 8:30�am, twisted <thenited...@yahoo.com> wrote:
>> On Jun 20, 9:02�pm, JJ <kariy...@nandomail.com> wrote:
>>
>>
>>
>> > One of your tires is bad. �Check for bumps or imperfections in the
>> > sidewalls.- Hide quoted text -
>>
>> > - Show quoted text -
>>
>> A bad tire will not make the brake pedal shake!
>
>...nor will a bad tire make the steering wheel shake under braking!
I hope you're being facetious. Otherwise I call BS.
HLS
> Contrary to that, I have also gone the route of meticulously torquing
> lugs, to find no notable difference between torqued lug nuts and those
> that weren't torqued.
Oh one more thing, in all the cases I have noted, the judder does not occur
immediately. It starts days to weeks after the action (new tires, pad
replacement,
rotation) which I believe initiates it. This, in my mind, supports warpage
with
heating of the rotor.
If you read the Babcox reports, they mention the problems of hub runout
and thickness variation. If that were the cause in these cases, one would
notice the shudder immediately. Thickness variation may be corrected by
machining the disc, but hub runout wont be - unless the rotors are machined
on the car.
And further they mention the possibility of shimming the rotor/hub, or even
indexing the rotor with respect to the hub irregularity, to minimize this
problem.
It is an interesting subject and, again, you can do what you want (but not
on
my cars ;>)
Mike Romain
Another Bad one for warped rotors from air hammers is Chrysler Jeep
products, they warp bad and easy.
Mike
2000 Cherokee Sport
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00
'New' frame and everything else in '09. Some Canadian Bush Trip and
Build Photos: http://mikeromainjeeptrips.shutterfly.com
Mike Marlow
"HLS" <nos...@nospam.nix> wrote in message
>
> "Mike Marlow" <mmarlo...@windstream.net> wrote in message
> news:abc03$4a3f7939$452897e0
>> Contrary to that, I have also gone the route of meticulously torquing
>> lugs, to find no notable difference between torqued lug nuts and those
>> that weren't torqued.
>
> Oh one more thing, in all the cases I have noted, the judder does not
> occur
> immediately. It starts days to weeks after the action (new tires, pad
> replacement,
> rotation) which I believe initiates it. This, in my mind, supports
> warpage with
> heating of the rotor.
>
I agree with this observation. I have concluded it to be related to
semi-metalic pads, as I don't see that now that I've switched everything
over to ceramics. I've also upgraded rotors that I use, but even with the
upgraded rotors, I found the problem could occur (only not as regularly)
with semi-metalics.
--
-Mike-
mmarlo...@windstream.net
ben91932
> Never assume. Let the shop/mechanic find teh problem.
Discuss your situation with a *quality* shop and go from there.
If you take your car in and ask them to machine the rotors and they
dont ask you why, never go there again!
A *good* shop will ask a ton of questions before service to determine
what will fix your car, and a *good* tech take the
75 or 80 seconds it takes to toss a mag base on before he tears it
down.
Finding a brake shimmy is auto shop 101 freshman year.
Dial indicator on the rotor, hub if necessary.
So many shops and customers are their own worst enemies...
HTH
Ben
ben91932
there is a tsb that says that rotor runout must be .002 or less...
Sounds like an on-the-car brake lathe would be best...
TSB # is 00-05-22-002L
HTH,
Ben
ben91932
This post sums up the sorry state of the industry quite well...
> I was merely explaining why the guy you go to (because he's good)
> doesn't win any friendship awards. Most of the time truly good techs
> work for less $ overall than the competing thieves, add to that - guess
> who undoes the previous failures, butchery, and needless parts
> shotgunning performed by said thieves? Then guess who the average
> customer thinks is the better mechanic? Naturally, the one armed with
> more BS advertising, flowery ass smoke, and (needless) parts sales. The
> real shop who charges 1 - 3 hours labor and $10 in wiring supplies (and
> actually spends that much time finding/fixing the difficult problem)
> can't even get this type of customer to come back for PM or "normal"
> repairs where a comfortable living can be made.
>
> --
> Toyota MDT in MO
Nate Nagel
I agree, in my particular case I am limited to two shops, if I take it
anywhere else I pay out of pocket. just wanted to post to see if anyone
had any other things to check just out of curiosity.
I will see if I can take it back on Wed. while I am in a meeting at the
office...
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
labatyd
"HLS" <nos...@nospam.nix> wrote in message
Somebody needs to give me the theory behind this phenonomon. The rim itself
has nothing to do with it. The only device which comes into contact with the
rotor is the caliper and pads. The piston side of the caliper should move
with fairly little pressure so scratch that idea. The whole caliper should
move if there were pressure on the outer side. Besides it would take a fair
amount of pressure to bend the rotor. Only if the rotor were loose and
something got behind to cause wobble after tightening then yes. The run out
of the rotor would wear the rotor surfaces on opposite sides and opposite
diameters, with consequent uneven thickness. Most of the rotors take some
effort to remove after a few years of service so I don't see tire service
causing problems. Finding a hub improperly machined from the factory is very
unlikely given today's manufacturing standards. Removing a rim for tire
service is not going to change the dynamics of the rotor.
Somebody has to show me an actual case before I'll buy it. I've been around
too long.
PeterD
>
>
>Somebody needs to give me the theory behind this phenonomon. The rim itself
>has nothing to do with it.
It has everything to do with 'it'... Remember, this is with alloy
wheels, not steel ones. There's a reason: steel rims are rather
flexible, alloy ones are not, the center hub is much more rigid.
>The only device which comes into contact with the
>rotor is the caliper and pads.
Oh, not in 99% of the vehicles on the road. Almost all have the rotor
sandwiched between the rim and the hub. Check yours, and you'll see
it. Exceptions are very exotic ones such as the Hummer H1 (inboard
brakes on all for corners), the vette, some Jaugar models, and some
high-end sports cars. Most common vehicles have rotors sandwiched just
as described.
>The piston side of the caliper should move
>with fairly little pressure so scratch that idea.
Humm...
>The whole caliper should
>move if there were pressure on the outer side. Besides it would take a fair
>amount of pressure to bend the rotor. Only if the rotor were loose and
>something got behind to cause wobble after tightening then yes. The run out
>of the rotor would wear the rotor surfaces on opposite sides and opposite
>diameters, with consequent uneven thickness. Most of the rotors take some
>effort to remove after a few years of service so I don't see tire service
>causing problems. Finding a hub improperly machined from the factory is very
>unlikely given today's manufacturing standards. Removing a rim for tire
>service is not going to change the dynamics of the rotor.
Virtually everything above is either outright wrong, or misstated.
>
>Somebody has to show me an actual case before I'll buy it. I've been around
>too long.
>
How long you have been around is insignificant if you stopped learning
at 15. But, hell, in your world everyone else is wrong and you are
right.
labatyd
"PeterD" <pet...@hipson.net> wrote in message
news:dik14515g0s4lm023...@4ax.com...
> On Mon, 22 Jun 2009 18:07:39 -0600, "labatyd" <fa...@fake.net> wrote:
>
>>
>
>>
>>Somebody needs to give me the theory behind this phenonomon. The rim
>>itself
>>has nothing to do with it.
>
> It has everything to do with 'it'... Remember, this is with alloy
> wheels, not steel ones. There's a reason: steel rims are rather
> flexible, alloy ones are not, the center hub is much more rigid.
OK so how does a rim affect the rotor in either case? As you state most are
sandwiched between. Forget exotic vehicles. How many of us drive such things
anyway?
>
>>The only device which comes into contact with the
>>rotor is the caliper and pads.
>
> Oh, not in 99% of the vehicles on the road. Almost all have the rotor
> sandwiched between the rim and the hub. Check yours, and you'll see
> it. Exceptions are very exotic ones such as the Hummer H1 (inboard
I know that.
> brakes on all for corners), the vette, some Jaugar models, and some
> high-end sports cars. Most common vehicles have rotors sandwiched just
> as described.
>
>>The piston side of the caliper should move
>>with fairly little pressure so scratch that idea.
>
> Humm...
>
>>The whole caliper should
>>move if there were pressure on the outer side. Besides it would take a
>>fair
>>amount of pressure to bend the rotor. Only if the rotor were loose and
>>something got behind to cause wobble after tightening then yes. The run
>>out
>>of the rotor would wear the rotor surfaces on opposite sides and opposite
>>diameters, with consequent uneven thickness. Most of the rotors take some
>>effort to remove after a few years of service so I don't see tire service
>>causing problems. Finding a hub improperly machined from the factory is
>>very
>>unlikely given today's manufacturing standards. Removing a rim for tire
>>service is not going to change the dynamics of the rotor.
>
> Virtually everything above is either outright wrong, or misstated.
>
You don't say WHAT's wrong.
>>Somebody has to show me an actual case before I'll buy it. I've been
>>around
>>too long.
>>
>
> How long you have been around is insignificant if you stopped learning
> at 15. But, hell, in your world everyone else is wrong and you are
> right.
On any of the common wheels most of us drive I've not seen it yet.
Thomas Tornblom
> "PeterD" <pet...@hipson.net> wrote in message
> news:dik14515g0s4lm023...@4ax.com...
>> On Mon, 22 Jun 2009 18:07:39 -0600, "labatyd" <fa...@fake.net> wrote:
>>
>>>
>>
>>>
>>>Somebody needs to give me the theory behind this phenonomon. The rim
>>>itself
>>>has nothing to do with it.
>>
>> It has everything to do with 'it'... Remember, this is with alloy
>> wheels, not steel ones. There's a reason: steel rims are rather
>> flexible, alloy ones are not, the center hub is much more rigid.
>
> OK so how does a rim affect the rotor in either case? As you state most are
> sandwiched between. Forget exotic vehicles. How many of us drive such things
> anyway?
I've had it happen to an ordinary audi with alloy wheels about 15
years ago. I had new tires installed and the shop had hammered the
wheels back apparently on full blast with the impact wrench, and I had
a terrible shimmy.
I tried to torque the wheels properly at home, but could not get the
bolts on one of the wheels loose. I cracked a socket trying to undo
the bolts.
I went back to the shop and with the long hose they had on the IW they
could not get the bolts loose without waiting for the compressor to
build full pressure in the tank. When they torqued the wheel properly
the shimmy was gone.
I always hand torque the wheels after this and I have never had a
problem with it again.
labatyd
"Thomas Tornblom" <tho...@Hax.SE> wrote in message
news:x04ou7y...@Hax.SE...
Obviously the wheel was mounted crooked. But the rotor wasn't damaged and
that's my point. But any reasonable person on a wrench should know enough
not to tighten one bolt to extreme. It doesn't require a torque wrench IMHO.
Of course as I've pointed out earlier in the thread any jockey may do the
job using a torque wrench and it relieves the shop of any consequences.
labatyd
"Thomas Tornblom" <tho...@Hax.SE> wrote in message
news:x04ou7y...@Hax.SE...
Just for the hell of it I'm going to take off (in turn) each front wheel of
my vehicles with disc brakes and retighten the rim to try to achieve what
you guys are telling me. I'll be watching very closely for any changes. I
don't expect any.
Thomas Tornblom
>
> Obviously the wheel was mounted crooked. But the rotor wasn't damaged and
> that's my point. But any reasonable person on a wrench should know enough
> not to tighten one bolt to extreme. It doesn't require a torque wrench IMHO.
> Of course as I've pointed out earlier in the thread any jockey may do the
> job using a torque wrench and it relieves the shop of any consequences.
>
No it was not. Just properly tightening the bolts one at a time to the
proper torque was enough to fix the problem. The wheel was not
removed, which would have been needed had the wheel been put on
crooked.
HLS
> of my vehicles with disc brakes and retighten the rim to try to achieve
> what you guys are telling me. I'll be watching very closely for any
> changes. I don't expect any.
If you retighten with an ordinary socket and BO bar, you probably wont.
The human brain and sense of feel will give an even slightly experienced
person some control.
Slam it on with an impact wrench, all rotored wheels, as if you were a
tire monkey. Watch it for a month or two. You may be lucky and you
may not.
PeterD
1. Goto barn.
2. Door was left open.
3. Check horse
4. Horse missing.
5. Close door.
6. Problem solved!
Not much of a test, there is nothing that says that the warpage would
correct itself if you did that. Only some evidence that in some cases
it helps.
Mike Marlow
"Thomas Tornblom" <tho...@Hax.SE> wrote in message
Not true. It would only require to loosen each lug nut a bit and retighten
them. I agree with labatyd - your experience is not the same as what is
being discussed.
--
-Mike-
mmarlo...@windstream.net
Mike Marlow
"HLS" <nos...@nospam.nix> wrote in message
Yeahbut that's not what's being discussed here. That's an extreme. I
realize you say you've seen this and I take your word for that, but I
haven't. Here's another side of this discussion - just the other day I had
to have a tire replaced. The mechanic threw the wheel back on the car and
ran it up with his impact - "hammering" each lug. But... his gun is set
very low, so the torque being applied to each lug is well under the torque
spec. To hear it, it sounds like he's just hammering the lug nuts on. He
grabbed the torque wrench when that was done and proceeded to get around a
quarter turn (or maybe a bit less), on each lug nut.
Those of us that don't use a torque wrench (I have used them, but do not use
them on any regular basis), have put them on with our impacts, and then
drove problem free for more than a month or two. That's the point of this
discussion - lots of folks don't use a torque wrench and have no problems,
either short term or long term.
--
-Mike-
mmarlo...@windstream.net
labatyd
Where does the warpage come from? You're sandwiching steel between steel.
There is nothing to give or bend. No gasket material between like installing
a head on an engine. If something got between then I can understand the
claim.
Rodan
........ just the other day I had a tire replaced. The mechanic threw
the
wheel back on the car and ran it up with his impact - "hammering"
each lug. But... his gun is set very low, so the torque being applied
to each lug is well under the torque spec. To hear it, it sounds like
he's just hammering the lug nuts on. He grabbed the torque wrench
when that was done and proceeded to get around a quarter turn
(or maybe a bit less), on each lug nut......
________________________________________________________________________
I bought two new front tires for my motor home at Sears in Fairfeld CA.
I was worried when I saw the tech hammering the lug nuts on with an air
gun. But then she went over the nuts with a torque wrench until the
wrench clicked so I felt more at ease. After 400 miles of driving, the
front end started wobbling. I discovered that five of the eight studs
on one front wheel were broken and the flopping wheel was attached
to only three studs.
I had just left the freeway when the wheel began wobbling. I was lucky
to be driving on a city street. or the result would have been much much
worse, for my motor home, for me, or for any one in my path. It was a
very costly experience, involving a tow, one new wheel and sixteen new
studs (only one broke on the other wheel but I had them all replaced).
Looking back, I realized that the technician had been too lazy to torque
the lug nuts correctly, so she had greatly over-torqued them with the air
hammer set too high, then applied the torque wrench only for show, to
get the click without actually turning the already over-torqued nuts.
Now I torque everything myself. If a technician has to torque my wheels
I stand and watch what he does. Then I re-torque them at home anyway.
Rodan. <----- Former Sears customer.
ben91932
> Where does the warpage come from? You're sandwiching steel between steel.
> There is nothing to give or bend.
They can both bend.
When you tighten a lugnut to 100 ftlbs, it can apply thousands of PSI
to the rotor/hub, more if using an impact wrench.
Steel, cast iron etc all bend easily under such forces.
HTH
Ben
ben91932
> I stand and watch what he does. Then I re-torque them at home anyway.
>
> Rodan. <----- Former Sears customer.
Wow...
Not to sound snarky...
Wouldnt it make more sense to take your car to a good place to begin
with?
I'm just sayin...
HTH,
Ben
Anyolmouse
"ben91932" <bente...@gmail.com> wrote in message
news:40c2f64f-9786-43da...@s38g2000prg.googlegroups.com...
The torque applied to the lug nuts does not have to bend /warp the
rotor. All it has to do is apply uneven pressure to the rotor. After
that heat will finish the job much the same as heating a metal plate or
rod while applying pressure to it. With the materials they are using
today it doesn't take a bunch of panic stops to do it. Heavy traffic,
coupled with the driver riding the brakes could well cause the problem.
My Safari started showing signs of warpage after the first aftermarkrt
brake job. I think I will buy all new OEM parts and do the job myself.
New rotors, drums, pads and shoes.
--
The only foundation of a free Constitution, is pure Virtue, and if this
cannot be inspired into our People, in a great Measure, than they have
it now. They may change their Rulers, and the forms of Government, but
they will not obtain a lasting Liberty.
John Adams, letter to Zabdiel Adams, June 21, 1776
Anyolmouse