Hum after rear-end gear change
88 Mustang GT Conv.
I've recently had my gears changed in my 1988 5.0L convertible to
3:73:1. (I only have 152,000KM on the car) There's a humming noise
which comes from the rear-end which gets significanltly louder between
60-90 KM / Hr.
I was told by the mechanic that this is a common thing with the gears
and should be ignored.
Just wanting to get some thoughts/opinions.
The mechanic I'm dealing with is great and has always done excellent
work on the car. He goes over and above what I've asked him to do with
little cost.
I'm just thinking that it should be normal as it can become quite
annoying.
Thanks in advance,
Marc
88 Mustang GT Conv.
wrote:
Just thinking that it SHOULDN'T be normal....sorry
John S.
wrote:
Doesn't sound normal to me... Some gears do whine more than others,
but by your brief description I get the feeling you are getting more
than normal.... Might want to get a second opinion from a reputable
gear shop if you have one in town...
elaich
a974-40e3-880...@m3g2000hsc.googlegroups.com:
> I was told by the mechanic that this is a common thing with the gears
> and should be ignored.
>
Then he is not the mechanic you think he is. Properly set up gears do not
make noise.
>
> The mechanic I'm dealing with is great and has always done excellent
> work on the car. He goes over and above what I've asked him to do with
> little cost.
>
> I'm just thinking that it should be normal as it can become quite
> annoying.
See above. A lot of otherwise competent mechanics do not have the knowledge
or tools to properly set the gear lash in a differential. You should take
the car to someone who specializes in working on differentials before
damage is done (if not already.)
WindsorFox<SS>
He's correct in that it is a fairly normal occurrence after new
gears are installed and not properly adjusted. That's why gear
replacement is something I had done, proper adjustment is critical and
not very easy.
--
TEACHER: Harold, what do you call a person who keeps on
talking when people are no longer interested?
HAROLD: A teacher
Michael Johnson
properly installed. Also, after he fixes this problem find yourself a
new mechanic.
88 Mustang GT Conv. wrote:
faus...@hotmail.com
>
> - Show quoted text -
I had 3.55 gears and trac loc put in my 69 coupe over 3 years ago. The
entire rear end was custom built by a shop that builds ford 9" rears
all the time for drag racing. So I know they know what they are doing.
They test drove it. I drove it home 300 miles. I drive it maybe couple
times a month in the summer time. Its made the whining sound ever
since they were put in over 3 years ago. They work great. Its more
noticable on the highway ofcourse. Im thinking that its fairly normal
for aftermarket gears. Ive never had a problem.
Michael Johnson
I had a set of 3.55s installed in my car and have never heard a peep out
of them. This is the way it should be for an 8.8 rear, IMO. Some whine
doesn't mean impending doom but it is typically an indication that
something is off to some degree. It is easy to tell if gears are not
wearing properly by looking at the wear patterns on the teeth.
WindsorFox<SS>
> Take the car back and tell him to fix it. Gears don't whine when
> properly installed. Also, after he fixes this problem find yourself a
> new mechanic.
>
The common thought, but I would be reluctant. I am very very picky
about by whom and how my Mustang is worked on (all my cars really) and
I'm not sure I'd want a half-ass like that going into it a second time.
What *I* would do is ask people that know, car clubs or at a race track
and get it readjusted then dispute the charge on my credit card. Go back
to the guy with proof that proper alignment fixed the problem and and
make him cut the bill in half at least. If he fails to comply I'd tell
him I was disputing the charge and taking him to small claims. He will
probably change his mind as long as you have proof that realigning the
gears fixed it and that is actually true. One has to assume you could
get a defective set of gears that is noisy and maybe it will go away,
maybe it won't. No car that I've had a gear replacement done to made
noise afterward.
WindsorFox<SS>
I have to wonder if the difference was the rear ends. I've never had
an 8.8 do what you are talking about, but the 9" rear is different with
the removable snoot, correct? The only car I have ever owned that made a
noise from the rear end was a 73 Charger that had the 8 3/4 rear that
also has the removable snooty on the front.
Dan
a974-40e3-880...@m3g2000hsc.googlegroups.com:
> I'm coming to all of you as the experts.
What brand were the gears? Ford gears have earned a reputation (at least
among the installers I know on- and off-line) for requiring the least
amount of adjustment and resulting in the least amount of noise after
installation. I know a couple of local installers that won't touch any
other brand because of the difficulties they've had in the past with other
aftermarket gears.
A little whine is not uncommon because of wear and tolerances in the
carrier. Sometimes it goes away, or at least gets quieter, as the gears
wear/break in.
However, something described as a "hum" doesn't sound right to me. The
worst noise should be an almost subliminal high pitch whine. More than that
means it's not shimmed right or something isn't meshing well.
Dan
P49Y83+
Dudly
"88 Mustang GT Conv." <marcbr...@rogers.com> wrote in message
news:a324e9b0-a974-40e3...@m3g2000hsc.googlegroups.com...
I had a rebuilt engine put in, went to solid mounts, new clutch, and they
changed out the oil in the rear end.
And ended up with a lot more drive train noise around 65 to 80 MPH, very
noticeable, in any gear with clutch engaged.
After driving it for a few months, it is gone.
I think the angle of engine to drive shaft was off. (only like 4 degrees or
so total)
If it was just gears, it should not have a resonance 60 to 90 km/hr, should
be noisy proportional to speed, seems like the tires/driveshaft would have
to be involved too.
Let us know what you fine out.
Zeke-baby
> I've recently had my gears changed in my 1988 5.0L convertible
> to 3:73:1. (I only have 152,000KM on the car) There's a humming
> noise which comes from the rear-end which gets significanltly
> louder between 60-90 KM / Hr.
>
> I was told by the mechanic that this is a common thing with the
> gears and should be ignored.
Let me guess. If you're cruising at speed with a light throttle,
and then lift your foot off the gas, the noise goes away (or gets
significantly quieter).
Sounds like it wasn't set up properly.
Cheers!
zėkė
--
'65 Fastback 289/4-speed/3.50s
'91 LX Hatchback 5.0/5-speed/3.08s (MIA since Feb'00)
'97 GT 4.6/5-speed/3.23s (the winter beater)
elaich
news:slrng92f5u....@news.motzarella.org:
> Sounds like it wasn't set up properly.
Pretty much what everyone in this thread has said.
The best way to go about it is to get a complete used differential/axle
with the ratio you want. Ford rear ends take a very long time to wear out.
The only one I ever had that made any appreciable noise was an 8" that had
over 600,000 miles on it. The 8.8 in my '71 Galaxie has over 240,000 on it,
and is quiet as a mouse.
On the other hand, mechanics who don't understand how to set a rear end up
properly (and they are few and far between now) can cause a lot of trouble
in a heartbeat.
I read over the procedure in my 1969 Chilton's book, and it isn't anything
I would want to tackle.
88 Mustang GT Conv.
wrote:
> 88 Mustang GT Conv. wrote:
>
> > I've recently had my gears changed in my 1988 5.0L convertible
> > to 3:73:1. (I only have 152,000KM on the car) There's a humming
> > noise which comes from the rear-end which gets significanltly
> > louder between 60-90 KM / Hr.
>
> > I was told by the mechanic that this is a common thing with the
> > gears and should be ignored.
>
> Let me guess. If you're cruising at speed with a light throttle,
> and then lift your foot off the gas, the noise goes away (or gets
> significantly quieter).
>
> Sounds like it wasn't set up properly.
>
> Cheers!
>
>
> --
> '65 Fastback 289/4-speed/3.50s
> '91 LX Hatchback 5.0/5-speed/3.08s (MIA since Feb'00)
> '97 GT 4.6/5-speed/3.23s (the winter beater)
This is exactly what happens. The noise is less significant (although
not gone) when the throttle is released.
To answer some other questions. The gears were provided by the
mechanic and I don't know the brand. I'm not a car buff (I like a nice
car but know little about them) and therefore rely heavily on other
people's knowledge experience.
The car is an automatic and I have 2" flowmaster exhaust (which make
enough noise on their own) and the humm overpowers them easily at that
speed range (with the top up or down).
Thanks to everyone, I will contact the mechanic and discuss with him.
Marc
Spike
Similar problem. Had the differential checked as a speed shop. Not a
thing wrong with the unit. When they put it back together, no sound.
The only change was the posi lube that gets mixed in. The speed shop
said to only use the Ford posi lube. Have not had a bit of problem
since. Nice and quiet. As I recall, and I can tell you what it calls
for, but they used 2 tubes of the Ford posi lube.
John S.
guessing you are talking about the "friction modifier"... helps the
clutches slip when you go around corners... without it they'll chatter
a bit..
WindsorFox<SS>
I think I'd get another mech to check it, someone recommended by
people from a track. Also 2" exhaust? THe stock Mustang pipes are 2 1/4"
the upgrade is usually 2 1/2 or 3"
WindsorFox<SS>
"Whale oil" There are synthetics of that stuff now by Amsoil and
Synergyn
88 Mustang GT Conv.
>
> - Show quoted text -
Sry...miss typed and didn't verify. I do have 3" pipes :)
Marc
Spike
Exactamundo! Kept trying to think of the term for that stuff and just
drew a blank. :0)
mech...@telusplanet.net
built the gearset is an expert, I have found that some gearsets are just
plain noisey.... Installation was performed using factory tools in
accordance with factory procedures and to factory specs.... and the gears
were noisy to some degree or another.... Another R&P, installed exactly the
same way, might give no noise at all...
The important thing to remember is that your mechanic MAY be the cause of
the noise... or he MAY be a victim of it..... There is no assurance that the
gearset was perfectly machined. Without knowing your mechanic nor what he
has for tools and/or skills.... there is no assurance that there is nothing
amiss with the installation.
The noise itself.... how loud is the hum????? Is it coming from the
gears???? (A dealer several miles away is having trouble with an 07 Mustang
GT - noise on decel.... three new gearsets and two wheel to wheel assemblies
and the noise is still there... ). My SuperCrew developed the dreaded "tip
in" gear whine while it was still under warranty.... I never did have the
time or shop space to have the concern addressed..... but it doesn't bother
me because playing the radio at normal volume makes the noise disappear....
How objectionable is your noise....
Now... before some of you guys try to rip my lips off.... I have no idea of
what any of you do for food..... But I dare you to tell me that you have
never.,.... EVER said "that's good enough...".
"88 Mustang GT Conv." <marcbr...@rogers.com> wrote in message
news:a324e9b0-a974-40e3...@m3g2000hsc.googlegroups.com...
Spike
To be honest, I can't recall ever having said "that's good enough",
although I might have. I DO know that on many an ocassion I have
said, 'screw this (or similar term)! I've had it/I need a break!'
Even, 'ta hell with it'. :0)
88 Mustang GT Conv.
> While everyone loves to blame the mechanic... obviously the boat-person that
> built the gearset is an expert, I have found that some gearsets are just
> plain noisey.... Installation was performed using factory tools in
> accordance with factory procedures and to factory specs.... and the gears
> were noisy to some degree or another.... Another R&P, installed exactly the
> same way, might give no noise at all...
>
> The important thing to remember is that your mechanic MAY be the cause of
> the noise... or he MAY be a victim of it..... There is no assurance that the
> gearset was perfectly machined. Without knowing your mechanic nor what he
> has for tools and/or skills.... there is no assurance that there is nothing
> amiss with the installation.
>
> The noise itself.... how loud is the hum????? Is it coming from the
> gears???? (A dealer several miles away is having trouble with an 07 Mustang
> GT - noise on decel.... three new gearsets and two wheel to wheel assemblies
> and the noise is still there... ). My SuperCrew developed the dreaded "tip
> in" gear whine while it was still under warranty.... I never did have the
> time or shop space to have the concern addressed..... but it doesn't bother
> me because playing the radio at normal volume makes the noise disappear....
> How objectionable is your noise....
>
> Now... before some of you guys try to rip my lips off.... I have no idea of
> what any of you do for food..... But I dare you to tell me that you have
> never.,.... EVER said "that's good enough...".
>
>
>
>
> > I'm coming to all of you as the experts.
>
> > I've recently had my gears changed in my 1988 5.0L convertible to
> > 3:73:1. (I only have 152,000KM on the car) There's a humming noise
> > which comes from the rear-end which gets significanltly louder between
> > 60-90 KM / Hr.
>
> > I was told by the mechanic that this is a common thing with the gears
> > and should be ignored.
>
> > Just wanting to get some thoughts/opinions.
>
> > The mechanic I'm dealing with is great and has always done excellent
> > work on the car. He goes over and above what I've asked him to do with
> > little cost.
>
> > I'm just thinking that it should be normal as it can become quite
> > annoying.
>
> > Thanks in advance,
>
> - Show quoted text -
Just an update....I picked up the car yesterday from the same mechanic
who completely accepted to look into the situation after I contacted
him about it.
The noise was loud enough that I could not drown it with the radio (I
couldn't have a conversation without having to raise my voice at these
speeds).
The mechanic has adjusted a few things and the noise is barely
noticeable (you really have to listen for it) and is in my opinion
"normal" (so far so good).
Like I said he is a great person and is an avid Mustang fan. He always
goes above and beyond and this time around proved that once again.
Thank you for all of your advice. It has helped me understand things a
little more and in the end my car is back in my driveway running well.
Regards,
Marc
Joe
> e9b0-a974-40e3-8...@m3g2000hsc.googlegroups.com...
I gotta ask - why the noise in the first place? If he test-drove it, he
certainly would've heard what you described (the radio wouldn't even
drown it out). If he didn't test drive it, then that's another story.
Spike
With mine, the more I drove it the louder and worse it got. Since the
addition of the posi lube, it's been over a year with zero "noise".
Sounds like the mechanic might, no matter how great a guy he is, have
forgotten to add the correct lube, or similar.
WindsorFox<SS>
>
> who completely accepted to look into the situation after I contacted
> him about it.
>
> The noise was loud enough that I could not drown it with the radio (I
> couldn't have a conversation without having to raise my voice at these
> speeds).
>
> The mechanic has adjusted a few things and the noise is barely
> noticeable (you really have to listen for it) and is in my opinion
> "normal" (so far so good).
>
> Like I said he is a great person and is an avid Mustang fan. He always
> goes above and beyond and this time around proved that once again.
>
> Thank you for all of your advice. It has helped me understand things a
> little more and in the end my car is back in my driveway running well.
>
> Regards,
> Marc
I'd really have to have asked why he didn't catch it in the first
place. And although the sounds like a good outcome, my rear end did not
make a barely noticeable, "you gotta listen hard to hear it" noise when
they installed the new rear, it made zero, just like the original. It
just sounds like he's guessing at the adjustment.
--
"While the fringe on one side hurl epithets at the fringe
on the other side, the vast bulk of us sit here somewhere
in between asking the eternal question, "What the fuck?" - TFrog93
Joe
news:11m3a496k5jsq2m2a...@4ax.com:
> On Tue, 12 Aug 2008 17:25:14 GMT, Joe <ho...@themoon.net> wrote:
>
>>"88 Mustang GT Conv." <marcbr...@rogers.com> wrote in
>>news:6381e917-e4ac-4135-b856-7c10fa6d7ac4
My experience has been that if the posi lube isn't added, things are
still fairly "normal" until you make a turn. Then it's more of a
chatter than a whine.
I still think the guy might not have adjusted them properly (not enough
time?), then when he got it back he had to do it right. Guess we'll
never really know...
Spike
>Spike <vee...@snowcrest.net> wrote in
>news:11m3a496k5jsq2m2a...@4ax.com:
>
>> On Tue, 12 Aug 2008 17:25:14 GMT, Joe <ho...@themoon.net> wrote:
>>
>>>"88 Mustang GT Conv." <marcbr...@rogers.com> wrote in
>>>news:6381e917-e4ac-4135-b856-7c10fa6d7ac4
>@c58g2000hsc.googlegroups.com:
>>>
>>>> On Aug 2, 2:30 am, <mecha...@telusplanet.net> wrote:
>>>>> While everyone loves to blame the mechanic... obviously the
>>>>> boat-person t
>>>> hat
SNIP
>>>> Regards,
>>>> Marc
>>>
>>>I gotta ask - why the noise in the first place? If he test-drove it,
>he
>>>certainly would've heard what you described (the radio wouldn't even
>>>drown it out). If he didn't test drive it, then that's another story.
>>
>> With mine, the more I drove it the louder and worse it got. Since the
>> addition of the posi lube, it's been over a year with zero "noise".
>> Sounds like the mechanic might, no matter how great a guy he is, have
>> forgotten to add the correct lube, or similar.
>
>My experience has been that if the posi lube isn't added, things are
>still fairly "normal" until you make a turn. Then it's more of a
>chatter than a whine.
>
>I still think the guy might not have adjusted them properly (not enough
>time?), then when he got it back he had to do it right. Guess we'll
>never really know...
"Chatter" might be one way to describe it. Long ago and far away,
there was a toy comprised of a string of squares held together with
cloth bands. When you flipped the top one over, like dominos, the rest
turned over with a CLACK CLKACK CLACK CLACK CLACK CLACK!
Now, that's sorta what it sounded like. You're right, mostly during a
turn with the left turn being far worse than the right, and when
backing. Not what anyone, especially the owner wants to hear!
Joe
news:nji4a45fqhc73odtv...@4ax.com:
Yeah, I remember something like that but I'll be damned if I know what
it was called. I'm not too far behind you in years...
> You're right, mostly during a
> turn with the left turn being far worse than the right, and when
> backing. Not what anyone, especially the owner wants to hear!
That's for sure. My Dakota has a limited slip, and if I let it go too
long w/o changing the fluid, the friction modifier loses some of its
effectiveness and the rear starts chattering on turns like a bunch of
chipmunks. First time I heard that I freaked, thinking the rear was
exploding. A quick trip to the dealer and a fresh fluid change with new
friction modifier made it as good as new.
