Help! Can't stop cupping on front tires!

banjopicker66 · Post by **banjopicker66** » October 16, 2007, 2:41 pm

I know this isn't on my Slick, but I need help. The front tires on my 2001 Dodge Ram 1500 4x4 are cupping badly, and I cannot seem to stop it. I have tried to research it, and can't find an answer.

The cupping is on the inside of the tire, as if the toe was pointed out. It is pretty evenly spaced around the tires, and is accompanied with feathering.

Single front solid axle (with internal shafts) not the later independent front suspension type with CV joints.

It has a shimmy at 20, but goes away only to re-appear worse at 40. It goes away again, but then returns as an on-off terrible vibration at 65-80.
New heavy duty gas shocks, wheels-tires balanced multiple times, highway (non-aggressive tread) and front alignment checked. Tires are not oversized, but are the recommended size. Ball joints are good. Driveline (front and rear) U-joints are good. No driveline noise. No fix-a-flat in the tires (I paid the tire place to pop the tires off to check!)

My son followed me on the freeway, and could not see any evidence of wheel imbalance, they looked like they were rolling true, even though I could feel it vibrating.

No fix to the cupping or to the vibrations, and it is getting worse.

Help!!????

Bills 66 · Post by **Bills 66** » October 16, 2007, 3:40 pm

Banjo
Drive your slick.

Have you checked your wheel bearings? My 98 1500 4x4 does not have that problem so I don´t believe it is a design issue.
Bill

Yellardawg · Post by **Yellardawg** » October 16, 2007, 3:50 pm

Ball joint

banjopicker66 · Post by **banjopicker66** » October 16, 2007, 3:51 pm

Bill: The front wheel bearings are new; they are the integral type, bolted to the spindle, and splined on the inside for the drive axles, much like front wheel drive front wheel bearings. Thanks for the idea though. It is really frustrating!

Uncle Skip · Post by **Uncle Skip** » October 16, 2007, 4:38 pm

Lower ball joint.. same problem on Mamma's expedition.
U@ss

DocDave · Post by **DocDave** » October 17, 2007, 9:49 am

Here's a stupid question and not meant to imply anything
Do you leave it in four wheel drive on the hiway?
Also shimmy could be caused by an alignment problem. But why just the inside of the tires? Bind up between the front and rear axle is a possible if you run in constant four wheel drive. You should see the problems on some of the dump trucks running in the pits here. They bind up so bad you cant move them unless you lift an axle and let the torque release
I agree with the lower ball joint being a possible, it explaines the inner tire wear.
Jusathought (or a half of one)
Dave

banjopicker66 · Post by **banjopicker66** » October 17, 2007, 9:59 am

Dave, good point, and no offense taken at all. I am desperate for a workable answer.
No, I rarely use 4x4, just in the winter when we lived in a little valley and couldn't get out. I will probably sell it when we finally get settled in SC, after the move.
Which explains why I am limited in what I can do right now; I am in SC with my home, family and tools in MD still.

Thanks for the input though. I'll check the ball joints again when I get the chance.

Slick Fan · Post by **Slick Fan** » October 17, 2007, 11:07 am

I bet if you took it to an alignment shop, the rack would point out what's worn pretty quickly. I'd guess ball joints too, or maybe even a tie rod.

shawns fords · Post by **shawns fords** » October 17, 2007, 11:59 am

I see you did have your alignment checked, and Adjusted as well? cupping on the tread can be from many things, one is not changing direction of the tread when rotating, sometimes a tar store will rotate them but only turn two of them around, I believe on 4x4 all four tires should be changed directions, they should be rotated in an X pattern instead of rears straight foward and fronts crossed to the back, if you look at your cupping pattern and see the edge towards the front of the tread is is up, and rear is worn down, thats the drive side, a tire gets more wear at the back of the tread where most of your power is applied and as time goes by that area will wear down more, usually this is due to lack of tire rotations. Turn the tire around and drive it, your drive side of your tread should be evened out after being driven for a while. This is something I had learned at ford Tech training school for noise vibration and harshness.
air pressures and worn parts can also be the culprit, but from your Post I would assume all these items have been looked at
I hope this will help
shawn

ICEMAN6166 · Post by **ICEMAN6166** » October 17, 2007, 12:38 pm

i was told when i bought the new winter tires for my 66 4x4 to rotate them every 5K miles or they would wear funny and develop spots and cupping issues. the tires are only used from Oct-April and do not get 5K on them in that time, but each year they are rotated from the previous position.

while driving in 4x4 on dry hard surfaced roads is not good, there is no issue with the hubs locked in and running in 2wd, especially around here and in the winter.

once a tire begins to cup, it no longer runs true on the road and therefore the cupping magnifies itself as time goes on.

many years ago i bought a new econoline van, around the time antilock brakes were first coming into use.
at 9K miles the tires on the front looked very bad, the rear were not good either.Ford put the blame on the tires, the tire company put the blame on Ford and the anti-lock brakes.neither would be of help.
i sold the van to get out of the headache.

Slick Fan · Post by **Slick Fan** » October 17, 2007, 7:02 pm

Missed the part of your story saying you had the alignment checked...I must be sleep reading again.

Sorry.

Ok, this will make me really feel dumb if I'm wrong...
Shawn, you're saying the tires should be rotated in an 'X' pattern. Maybe it's just an old wives' tale I learned years ago, but I had been told that with radial tires, if you put them on the opposite side of the vehicle...making them spin the opposite direction they have been spinning for so many thousand miles, you run the risk of belt separation.
I've known that rotating in the 'X' pattern is safe for bias plies, but with radials, you're just supposed to switch them front to rear. Am I wrong?

shawns fords · Post by **shawns fords** » October 17, 2007, 7:13 pm

Iceman, I remember a concern back in the mid 90s with Econolines having excessive tread wear from the fronts. most of this was on Econolines that were used for Work, construction, type of vehicles, what we found was the vans would actually fall out of alignment when the van is loaded down with a heavy load of extra weight in the back, sometimes they would be hauling a trailor 90% of the time as well, this caused the problem, so Our alignment guy, (who I worked next to for years, and taught me most of this) would correct it on the rack to fix the excessive tire wear.

Slick I dont know anything about bias ply tars, I learned to change tread pattern on all fours in an X pattern due to the fact your driven side of the rubber is being eaten away slowly which is where most cupping comes from, I have seen many belts broken but never from changing the direction of the tread, unless its a directional tire which would have a tread pattern made to run in only one direction. I crossed my BFG all Terrains on my 96 F250 and lasted 60k with them rotated every 10k as long as I could remember when that 10k was up, lol I think I went 20k a couple of times also.

blackagatha · Post by **blackagatha** » October 17, 2007, 10:10 pm

I don't know the specifics, but my dad said that when radials first came out, reversing direction WAS a problem...

Apparently, when new, they could be put on in either direction, but as they got used, the belts shifted in the "drive" twist, presumably in the same effect that causes cupping... If you reversed them, the belts would begin to stretch the other way, making (slack--I believe) at some point, resulting in failure...

I don't know how they are different now, but they are supposedly good to swap however you see fit...
Good for me... There is to be no front-back swapping for me, as I got fatties and skinnies...
The rears get swapped every once in a while due to the wear on the right rear... "no idea why...." Fronts are still like new, get flipped about every time thee rears get changed, although I think they are not nearly as critical... Rears are coming due to get replaced.... Disappointed that they went away so fast, but it's "operator error".... haha

Slick Fan · Post by **Slick Fan** » October 18, 2007, 12:46 pm

blackagatha wrote: Apparently, when new, they could be put on in either direction, but as they got used, the belts shifted in the "drive" twist, presumably in the same effect that causes cupping... If you reversed them, the belts would begin to stretch the other way, making (slack--I believe) at some point, resulting in failure...

That's the scenario I've always known to be true, so I've never rotated them side to side. I suppose the radial technology may have changed through the years, allowing side-to-side swapping without risking belt separation. Maybe I'll give it a try on my daily driver & see what happens.

Now & then, I'll buy 'take off' tires that are in good shape & they are almost NEVER marked as to which direction they were on. Sometimes I have a belt separation on one of those, but not often.
Thanks for your reply, Shawn.

ELpolacko · Post by **ELpolacko** » October 18, 2007, 6:52 pm

My educated guess here:

First things to check are the ball joints, classic lower ball joint degradation....

BUT

The same symptoms can arise from toe out with worn out shocks! Most modern trucks run low toe in angle to slow steering input reactions. When everything is in good shape and tires are rotated regularly the wear is not noticeable. Compound that with a "comfort" shock that has little or no dampening reaction for over a 1/2" of wheel travel and you get cupping.

I would also check for wear on the steering system and components.

TnCobra · Post by **TnCobra** » October 21, 2007, 7:21 pm

I have the exact same truck and had a cupping problem as well, I bought my truck new in 01' and it came with Michelin street tires, when they cupped, and cupped badly I might add, I bought Yokahoma Geolander AT tires for it and havent had any problems of any kind with the tires since. May not be your fix, but sure was mine.