Tires wearing strangely

[ChallengerHK]

First up, this is for a friend who has an 07 Civic. The car was in an accident a few months back, in which he was hit from the front right and the front clip was pushed to the left by several inches. I was sure that they'd total the car, but the insurance company opted to "fix" it.

So, his tires are wearing in ways that I have never seen. Two examples:

1) The left front tire has odd wear on the shoulder between the sidewall and the tread. Roughly speaking, about 270 degrees of the shoulder is fine, but one section of roughly 90 degrees has the should almost completely worn away, making the sidewall "roll in to" the tread without any real edge separating them. If it was happening all the way around the tire I'd say "alignment," but it's only part of the tire, and it's pretty severe.

2) On the right front, there are small areas around the inner tread ring that are worn almost through the tread. These areas are roughly 4 inches square each. Tread around them builds up as you get farther from the wear area until, say, 6 inches away there's a quarter inch of tread. Again, if this was happening all the way around that tread ring I'd say it was alignment, but it's in localized, specific areas.

My only potential thought is that the wheels were damaged and the runout has been changed, essentially "flat-spotting" the wheels and causing them to exert different pressure on the tire against the ground depending on where the tire is in its rotation.

Any other ideas?

[HP2]

Well, typically shoulder wear is bad camber settings. The cupping type of wear that hits only selective spots around a tire can be an out of balance condition on the wheel or bad shocks. Since this is an accident repair, it likely is a combination of things.

[ChallengerHK]

Thanks, HP. I'm assuming that

- if it were caused by a bad alignment that it would happen all the way around the tire
- that struts are tested the same way as shocks, i.e., by bouncing the vehicle and seeing it it continues to bounce more than one cycle

Are these good assumptions? (It did pass the bounce test, BTW.)

[MEK-Dangerfield]

I want to say the wheels are the problem, but wouldn't there be some kind of vibration at high speed to go along with that theory?

[ChallengerHK]

Thanks for reminding me about that, Mike. He does have a high speed vibration, but it's relatively subtle.

[NoMope Greg]

I agree with HP that the "cupping" is from an out-of-balance issue.  With an '07, it's not likely from the shocks.  It may also have run-out issues, since it was hit on that side, assuming they didn't replace the wheel to begin with.  There may also be an alignment issue (camber) there, since the wear pattern is uneven across the tire section.  Has he had the alignment and run-out checked by a competent alignment shop?  He might want to look for one that does dyanamic alignment, in which the alignment and balance are checked with the wheels on the car.  It's more expensive, but done properly, it can make a big difference in pinpointing the source of the problem.

One easy way to see if it's the wheels or the suspension is to rotate the tires.  If the wear pattern follows the wheel, then the problem is in the wheel.  If it doesn't, the issue is in the suspension.  But I'd start by replacing the tires and having the suspension re-aligned.

[DAYLEY/CHALLENGER]

Is the car..........dog tracking???

[Bullitt-]

I'm thinking problem #1 may be a separated belt...was this tire in the accident?  I was surprised when the adjuster put 2-new tires on an estimate a few years ago, body shop guy said they had to since the rims were damaged something to do with safely & liability. 

[ChallengerHK]

Thanks for the help, guys.

Re: a balance issue, what's the weight on those flat stick-on weight that are about a half-inch square? Three of his wheels have 15-20 of those weights on them, but the fourth wheel only has 5.

Dog-tracking, Dave? Is that like crabbing? Body sideways when wheels are straight?

Re: the cupping, what else would cause that?

[HP2]

Cupping could be caused by a bent or out of balance wheel that has a non linear ossicilation. The same could happen with shocks, which could perform decently when pushed an inch or two during suspension movement, but have enough internal damage (blown seals or plugged orifices) to not be able to control the wheel oscilations that only move the shock slightly. Another thought, since this is an accident repair, is bent or out of balance half shafts. They are unlikely suspect, but if the car eats wheel bearings in another 10-15k miles, they are suspect as well.

Wheels weights, any wheel that requires 15-20 weights has a major issue. Could be stack up of wheel imbalance and/or tire imbalance. One or both of those pieces should be ditched. At the least, the tire shold have the bead broken and the tire rotated 90* to see how the imbalance moves.

Dog tracking, dog legging, crabbing are all similar conditions. You would need to have someone follow the car down a straight road to see it and even then, slight variations may not be obvious.

[ChallengerHK]

Thanks again, HP.

I suspect he's going to have to go back to his insurance company and tell them that the car is just not right.

[Super Blue 72]

Wheels weights, any wheel that requires 15-20 weights has a major issue. Could be stack up of wheel imbalance and/or tire imbalance. One or both of those pieces should be ditched. At the least, the tire shold have the bead broken and the tire rotated 90* to see how the imbalance moves.

Dog tracking, dog legging, crabbing are all similar conditions. You would need to have someone follow the car down a straight road to see it and even then, slight variations may not be obvious.

   That many wheels weights sounds pretty bad.  I assume it's acompetent person who did the balance, as I'm reminded of a guy who balanceed my wheel and did not take off the old weights.  I'm surprised that if the wheels took that much weight the mechanic didn't say something about the wheels being bent or odd that it need so much weight.

As far as the dogglegging, justa  thought maybe if someone is following behind the car might be an idea to also have that person observe the car from the side when the car is getting the vibration to see if the wheels are oscillating from possibly damaged struts from the accident.  Sometimes the bounce test doesn't work that well. 

Just for clarification, was the car hit from the side or from an angle from the front?  Were both front tires replaced.

[DAYLEY/CHALLENGER]

Dog-tracking, Dave? Is that like crabbing? Body sideways when wheels are straight?

Re: the cupping, what else would cause that?

Well.......sometimes when you follow a tractor trailer down the road and you can see the cab on the drivers side and the trailer is running off the right side of the road......that is a severe case of dog tracking.  I sometimes meet cars that are that way.  Side ways  collisions can move the rear end so that the measurement from the center of the front tire  to the center of the rear tire on the same side is different onthe other side of the car. 

This is a tractor trailer example...........it would not let me copy the pics...

It is important to note that the 'total vehicle' should be properly aligned, not just the front axle. Industry experts generally agree that alignment of the drive axles in a tandem configuration is also critically important for the vehicle to achieve proper tracking. There are two basic ways that drive axles can be misaligned. In one case, if both axles are parallel but are not perpendicular to the vehicle centerline, then a resultant "thrust" angle is created. As shown in Figure 4, the drive axles try to push the vehicle away from the centerline.



If the drive axles are not parallel, then the situation is described as a "scrub" angle problem. In this case, the drive axles are trying to turn the vehicle. In either case, to bring the truck's travel back into a straight line, the driver has to provide an opposing steering input. This need for continual correction can induce driver muscular fatigue, as well as increased tire wear and reduced fuel economy.

[ChallengerHK]

Re: the wheel weights and the alignment, I suspect that the insurance company "suggested" to the technician/ frame shop that the wheels were fine. They're alloy, pricey (something like $800 each new). I know that the wheels weren't replaced, but I don't think the tires were replaced either.

I like the idea of following and observing. May get his wife to drive wing with me in the car to observe.

So, in doglegging, the frame kind of describes a parallelogram?

I think it was hit almost head-on from the side. If I recall all of this correctly, he was pulling into an intersection after a light turned green and a guy on the cross-street ran the red and smacked him almost straight on t-bone. Still, like I said the clip was displaced by a few inches, so even straight on the damage was substantial. I figured that there would be wheel damage and possibly engine/trans damage in addition to the clip, so I was sure they'd write it off.

[DAYLEY/CHALLENGER]

 the frame kind of describes a parallelogram...................Yep............thats her..............

Hope the north is treating you well.   I go by your house  once in a while.  Still has the for sale sign.  Someone bought the house on the left side..........