Tires-cupping
Sue milham
tires, and the diagnostics of which parts of the tire are affected? I'm
thinking alignment, but when that is showing within tolerances, what else??
I seem to be doing this month's LIFE DISERTATION on tire wear!
TIA,
Sue M.
David Osborn
Sue,
The tires are cupping because they aren't maintaining steady contact with the
road. The most likely cause is bad shocks (or struts) allowing wheel "hop" as
you drive. However, it's also possible that there's some other component worn
so badly that the wheel has some other sort of motion it shouldn't have. It's
also possible that a severe out-of-balance condition could be responsible for
it.
What does it feel like as you drive? Do you have unusual vibration in the
steering wheel? Do you feel any other unusual sensations?
- - - - -
David, N8DO; FMCA 147762
djosborn at aol dot com
W F Sill
>Well maybe I don't understand the basics. What exactly causes cupping of the
>tires, and the diagnostics of which parts of the tire are affected? I'm
>thinking alignment, but when that is showing within tolerances, what else??
Cupping (uneven tread wear around the circumference might be more
descriptive) _can_ result from poor alignment and/or incorrect
inflation, but is more likely to arise from imbalance, loose wheel
bearings, and/or bad shocks. Certainly there can be other causes but
those are most likely.
Once it gets a good start it tends to feed on itself and there are
really only a couple of sure-fire ways to get rid of it once the
underlying problems are solved: machining off rubber, or replacing
the tires.
Will Sill KD3XR
"There is a way that seems right to a man, but
in the end it leads to death" Prov 14:12 NIV
Larry
alignment.
Alignment causes handling problems and tire wear on the inside or outside
edges.
Balance would generally cause a vehicle and/or steering wheel vibration at
given speeds.
W F Sill <wi...@epix.net> wrote in message
news:r8k1ts0ib5l3krhq5...@4ax.com...
Sue milham
around right handed curves, which I have to do to and from town.
This is my Camry, low mileage and still tight, had it checked today again for
worn or bent components, and they couldn't find anything.
I also got this cupping with my Class C, then it did turn out to be alignment.
We moved the offending tire to the rear and it didn't recur. But with the
Camry it just continued degrading tires after alignment, and got 3 of the 4
tires.
I guess it's the front wheel drive suspension that is not as solid as a rear
wheel. I get 4 new tires tomorrow to see if it cures the problem, since the
alignment is supposed to still be within specs, even tho' it continued to ruin
the tires once they started cupping. They also calll them "dipped out" here in
the South.
I know this is not RV, but here I could get some expertise.
I'll be the proud owner of two sets of Firestones. Wish me luck on the
highways.
Thanks for your ideas.
djos...@aol.commnet.net (David Osborn) writes:
>Sue,
>
>The tires are cupping because they aren't maintaining steady contact with
>the
>road. The most likely cause is bad shocks (or struts) allowing wheel "hop"
>as
>you drive. However, it's also possible that there's some other component
>worn
>so badly that the wheel has some other sort of motion it shouldn't have.
> It's
>also possible that a severe out-of-balance condition could be responsible
>for
>it.
>
>What does it feel like as you drive? Do you have unusual vibration in the
>steering wheel? Do you feel any other unusual sensations?
>
>- - - - -
>David, N8DO; FMCA 147762
>djosborn at aol dot com
Sue M.
Sue milham
After the right front tire got cupped the car started pullling to the Left, so
I guess that is the handling. All this points to alignment, tho' one was done
when the new tires were installed replacing the old cupped ones. How do we
know when we are getting the proper service? It seems a simple procedure to
follow an alignment machine. But then one would have to be alert and
interested in the job. I'm finding that decreasing in mechanics and the
maintenance of my vehicles suffers and so does my pocketbook. As far as I know
nobody will warrant an alignment. And I don't think I can do it myself.
Thanks for the ideas.
Sue M.
David Osborn
>The cupping IS on the edges, no vibrations.
>
>After the right front tire got cupped the car started pullling to the Left,
>so
>I guess that is the handling. All this points to alignment, tho' one was
>done
>when the new tires were installed replacing the old cupped ones. How do we
>know when we are getting the proper service? It seems a simple procedure to
>follow an alignment machine. But then one would have to be alert and
>interested in the job. I'm finding that decreasing in mechanics and the
>maintenance of my vehicles suffers and so does my pocketbook. As far as I
>know
>nobody will warrant an alignment. And I don't think I can do it myself.
>
Sue,
Why do you keep talking about alignment and cupped tires when several people
have to you to look elsewhere for othe worn items? You need to find a good
mechanic. If you don't know one, then ask your friends until you get a good
recommendation.
We can't completely diagnose your problem from a distance, and you'll never
find it unless you find competent mechanic you can trust.
Gary L. Smith
properly?
"David Osborn" <djos...@aol.commnet.net> wrote in message
news:20000927064229...@ng-fo1.aol.com...
> suem...@aol.com writes:
>
> >The cupping IS on the edges, no vibrations.
> >
> >After the right front tire got cupped the car started pullling to the
Left,
> >so
> >I guess that is the handling. All this points to alignment, tho' one was
> >done
> >when the new tires were installed replacing the old cupped ones. How do
we
> >know when we are getting the proper service? It seems a simple procedure
to
> >follow an alignment machine. But then one would have to be alert and
> >interested in the job. I'm finding that decreasing in mechanics and the
> >maintenance of my vehicles suffers and so does my pocketbook. As far as
I
> >know
> >nobody will warrant an alignment. And I don't think I can do it myself.
> >
>
sgfocus
the tires. Went to Goodyear about it and they informed me that the tires
hadn't been properly rotated. They should be rotated every ten thousand
miles in order to avoid cupping.
George.
"Sue milham" <suem...@aol.com> wrote in message
news:20000926114237...@ng-md1.aol.com...
> Well maybe I don't understand the basics. What exactly causes cupping of
the
> tires, and the diagnostics of which parts of the tire are affected? I'm
> thinking alignment, but when that is showing within tolerances, what
else??
>
> I seem to be doing this month's LIFE DISERTATION on tire wear!
>
> TIA,
> Sue M.
Larry
good mechanics out there and they really do try to do the best job they can.
The problem seems to be that a lot of places that do all around general
repairs have mechanics that don't seem to know their jobs very well (not all
but a lot). That is why I feel it is best to go to a specialty shop for work
like front ends. It may cost more but you are dealing with people that do
that type work as their living day in and day out.
Also, with a problem like you are talking about it would be good for the
mechanic to be able to see the actual tires that are worn. Sometimes that
can give them a good indication of what the problem might be. Having
technical training in front end alignment, I know there are a lot of things
that can effect how a car handles and how tires wear. Even a very heavy
person on one side of a car the majority of the time can necessitate setting
up the front end a little differently from just factory specifications so
the best results are obtained.
Lastly, ask about a warranty on the work before you get it done. They should
be willing to recheck it if you feel you are having a problem and charge you
nothing to do it.
Good luck with your problem and I hope you get it fixed correctly.
David Osborn <djos...@aol.commnet.net> wrote in message
news:20000927064229...@ng-fo1.aol.com...
> suem...@aol.com writes:
>
> >The cupping IS on the edges, no vibrations.
> >
> >After the right front tire got cupped the car started pullling to the
Left,
> >so
> >I guess that is the handling. All this points to alignment, tho' one was
> >done
> >when the new tires were installed replacing the old cupped ones. How do
we
> >know when we are getting the proper service? It seems a simple procedure
to
> >follow an alignment machine. But then one would have to be alert and
> >interested in the job. I'm finding that decreasing in mechanics and the
> >maintenance of my vehicles suffers and so does my pocketbook. As far as
I
> >know
> >nobody will warrant an alignment. And I don't think I can do it myself.
> >
>
David Osborn
>Agreed. Then again, don't condemn all mechanics for what some do. There are
>good mechanics out there and they really do try to do the best job they can.
>The problem seems to be that a lot of places that do all around general
>repairs have mechanics that don't seem to know their jobs very well (not all
>but a lot). That is why I feel it is best to go to a specialty shop for work
>like front ends. It may cost more but you are dealing with people that do
>that type work as their living day in and day out.
>Also, with a problem like you are talking about it would be good for the
>mechanic to be able to see the actual tires that are worn. Sometimes that
>can give them a good indication of what the problem might be. Having
>technical training in front end alignment, I know there are a lot of things
>that can effect how a car handles and how tires wear. Even a very heavy
>person on one side of a car the majority of the time can necessitate setting
>up the front end a little differently from just factory specifications so
>the best results are obtained.
>Lastly, ask about a warranty on the work before you get it done. They should
>be willing to recheck it if you feel you are having a problem and charge you
>nothing to do it.
>Good luck with your problem and I hope you get it fixed correctly.
Larry,
I didn't mean to "condemn all mechanics" in any way. There are, of course,
some very good ones -- and some very bad ones -- out there. I simply was
indicating that she should find one she can trust, and establish a relationship
with him. She seems to be "chasing her tail" on this one, and I think a good
mechanic could quickly get to the root of the problem.
Ben Fullerton
: I purchased a light duty F250 with the same cupping problem on the inside of
: the tires. Went to Goodyear about it and they informed me that the tires
: hadn't been properly rotated. They should be rotated every ten thousand
: miles in order to avoid cupping.
: George.
What was that that someone was saying about incompetence?
Good tires on a properly designed and maintained vehicle do not cup!
Rotation is just a way of covering up the problem and spreading it around
so that it is not so noticeable.
Before you jump all over this one - I am a certified mechanic and have
driven a wide assortment of vehicles for a total of well over a million
miles. I was *always* able to identify a cause for any tires that showed
even minimal cupping.
Ben F.
Sue milham
be needing heavy duty suspension work. I'm using the same dealer that I have
for 12 years or so, 20 years with my Class C, I find the mechanics more pressed
for time, fewer workers to spread the load. Sorry, the car was off topic, but
it seems like with toads et al,that this was the most expertise group to try to
figure out this mystery. The problem of cupped tires does come up with rvs
too. And I was answering a post. But I'll just let it go, if no one else is
interested.
> djos...@aol.commnet.net (David Osborn)
>Sue,
>
>Why do you keep talking about alignment and cupped tires when several people
>have to you to look elsewhere for othe worn items? You need to find a good
>mechanic. If you don't know one, then ask your friends until you get a
>good
>recommendation.
>
>We can't completely diagnose your problem from a distance, and you'll never
>find it unless you find competent mechanic you can trust.
>
>- - - - -
>David, N8DO; FMCA 147762
>djosborn at aol dot com
Sue M.
David Osborn
Wonder if that F-250 had Ford's infamous "Twin-I-Beam" front suspension?
Sue milham
they say once a tire has started to cup, it's a done deal. Tho'on my Class C,
we moved the offending tire to the back after an alignment and none of the
others have cupped.
You know, there just don't seem to be many front end shops around here anymore.
The old guys went out of business and few seem to know suspension these days.
They mostly seem to rely on computers to tell them the whole story, rather than
experience, as you say.
Thanks for your interest and advice, I will continue to research the tire
problem and learn more about it myself, as I think that I am the one to monitor
the progress.
BTW while I was hanging around the Firestone store, I over heard the reports
that most of the bad tires came in underinflated at 25-26psi, and they think
that is definitely the cause of the tread separation. I found the same
diagnosis in an old auto mechanic book of mine.
Happy Travels,
Sue M.
Sue milham
poor design, in some of the professional's estimatation who I asked. Are any of
the rvs front wheel drive?
>ac608...@chebucto.ns.ca (Ben Fullerton)
>What was that that someone was saying about incompetence?
>
>Good tires on a properly designed and maintained vehicle do not cup!
>
>Rotation is just a way of covering up the problem and spreading it around
>so that it is not so noticeable.
>
>Before you jump all over this one - I am a certified mechanic and have
>driven a wide assortment of vehicles for a total of well over a million
>miles. I was *always* able to identify a cause for any tires that showed
>even minimal cupping.
>
>Ben F.
Sue M.
Ben Fullerton
: With this car at only 49,000, most highway driving, practically new, should not
: be needing heavy duty suspension work. I'm using the same dealer that I have
: for 12 years or so, 20 years with my Class C, I find the mechanics more pressed
: for time, fewer workers to spread the load. Sorry, the car was off topic, but
: it seems like with toads et al,that this was the most expertise group to try to
: figure out this mystery. The problem of cupped tires does come up with rvs
: too. And I was answering a post. But I'll just let it go, if no one else is
: interested.
: Sue M.
Don't let one person's disinterest (lack of answers for the question?) put
you off. Others here may well be interested in the problem - for the day
when it might happen to them.
I don't have a specific answer via long distance but will make a
suggestion or two.
It is probably NOT one single problem, but a combination of two or maybe
even more. Checking for problems one at a time might reveal something that
would not, by itself, cause tire cupping. Put that problem together with a
another one or two *minor* problems and the combined total can be very
different.
I would suspect that the little things could include:
- alignment (yes, it *can and does* contribute strongly to tire cupping),
- slack in any of; wheel bearings, control arm bushings (not familiar
with the details of your car's suspension), tie rod ends or other steering
gear joints, steering rack mounts,
- wrong (below the correct pressure for the load) tire pressure,
- wheel balance,
- defective tires (low probability),
- ...... and a few more things that I will think of *after* I push the
"send" button. :-)
I could write a page or two on each of the above - but I think *that*
probably *would* be seen as overdoing it on this ng. :-)
Ben F.
Hugh Darling
miles. It is on it's second set of tires. Neither the first set or the
present set has ever been rotated and they frequently were run with low
pressure (my wife drives it but never checks anything). The tires have
never cupped. One front tire was run low too long and wore to the belt
on the inside. I think the Toys have pretty bullet proof suspensions.
Ours is not a toad however and I would put some weight to rotating the
tires. Don't recall if it's been mentioned yet, is the tow bar
horizontal to the ground or is it slanting up towards the MH? If it is
slanted uphill, the tow bar could be lifting the front suspension
causing a change in the front end geometry.
Hugh
Sue milham wrote:
>
> With this car at only 49,000, most highway driving, practically new, should not
> be needing heavy duty suspension work. I'm using the same dealer that I have
> for 12 years or so, 20 years with my Class C, I find the mechanics more pressed
> for time, fewer workers to spread the load. Sorry, the car was off topic, but
> it seems like with toads et al,that this was the most expertise group to try to
> figure out this mystery. The problem of cupped tires does come up with rvs
> too. And I was answering a post. But I'll just let it go, if no one else is
> interested.
snipped