Alignment/suspension issue (pics)?

[Quattro Pete]

What sorts of issues am I looking at here, judging by this tire wear?

This is the left rear tire on my BMW in the sig. About 14K miles on the tires. They were rotated, but apparently not often enough as the fronts still have plenty of tread left, but the rears are at wear bars, and this left rear is particularly shot. The inner shoulder wear is no big deal - typical BMW negative rear camber, but surprisingly, the right rear wore pretty evenly by comparison. What worries me is that completely bald patch in one area of the tread.

If I recall, that one tire had a bit of a high speed vibration for some time. It ended up being an imbalance issue that has gone untreated for a while. Not sure if that could account for this bald patch or if it's some suspension issue. Any thoughts?

For comparison, below is the right rear tire that wore quite evenly, but is still at wear bars and will be getting replaced come Spring of next year.

 

[Drew99GT]

Excessive negative camber? Take it to a good alignment shop and see what's wrong. Could be many things; worn suspension bushings or the alignment is just out of whack from rough roads.

 

[Quattro Pete]

Originally Posted By: Drew99GT
Excessive negative camber?

Like I wrote, negative camber kind of comes with the territory here, although I agree that it could be brought a bit closer to 0.

But what about that one completely bald spot? Can you guys see it? I can circle it if it's hard to tell what I'm talking about...

 

[JHZR2]

Are those Bridgestone RE970 or similar? Surprised because mine wore like iron on my Saab. That's a lot of wear and an irregular pattern.

That said, my w123 MBs have often "scalloped" the outer tread blocks in a repeated pattern. You can confirm that this bald spot is not a pattern, just a single spot? Other side tire is the mirror image overall wear wise (perhaps minus the bald spot)?

 

[Quattro Pete]

Originally Posted By: JHZR2
Are those Bridgestone RE970 or similar? Surprised because mine wore like iron on my Saab. That's a lot of wear and an irregular pattern.

Yes, these are RE970. I had RE960 before, and they seemed to have lasted a bit longer than these.

Quote:
You can confirm that this bald spot is not a pattern, just a single spot? Other side tire is the mirror image overall wear wise (perhaps minus the bald spot)?

Yup, just a single spot.

 

[Drew99GT]

Looks like cupping perhaps from worn shocks??? Under inflation?

 

[Drew99GT]

http://www.renoscca.org/forums/showthread.php?t=1164

Could be a tire with a bad belt. Did it vibrate or was it hard to balance?

 

[Quattro Pete]

Originally Posted By: Drew99GT
Did it vibrate or was it hard to balance?

When I first bought them, there was no vibration. They balanced out well.
Some time later in their life, that particular tire developed a high speed vibration, and I neglected to get it checked out right away. Then, several thousand miles later, I finally did get it re-balanced and the vibration went away.

 

[CT8]

Go to a front end shop where the workers have more skill than to set the toe and let it go. !

 

[jjjxlr8]

If it's truly only in one spot around the circumference, it's not your suspension. It's the tire.

 

[spasm3]

I would guess it was run out of balance.

 

[Merkava_4]

Originally Posted By: CT8
Go to a front end shop where the workers have more skill than to set the toe and let it go. !


A lot of people don't know what a front end shop is; the OP probably doesn't know either. It's a shame these people always go to a tire shop for an alignment.

 

[Quattro Pete]

Originally Posted By: Merkava_4
Originally Posted By: CT8
Go to a front end shop where the workers have more skill than to set the toe and let it go. !


A lot of people don't know what a front end shop is; the OP probably doesn't know either. It's a shame these people always go to a tire shop for an alignment.

Hold your horses. My last alignment was done at a BMW service center. They followed all the required steps... full tank of gas, weights placed in various parts of the car, etc.

Granted, it's been a while, so I may need to have it done again.

 

[bdcardinal]

If you run your hand on the tire does anything feel out of place? Usually a spot like that is something internally wrong with the tire. On a track tire I would say a braking flatspot, however those are usualy more in the center of the tread.

Alignment looks like the typical negative camber that BMWs run on the rear.

 

[40w8]

Considering that the other rear didn't do that, and lots of negative camber is normal on most modern cars in the rear; I'd say that the belt inside tire let go.

I had a front tire do that once, and I was sure it needed alignment, but was loose belt on one side of tire.

The worn spot and vibration sort of tells that.

Put a new tire which you need, and don't worry about alignment, but keep checking with tread depth guage.

Camber isn't a very bad wear factor although toe is.

I've got a staggered tire BMW X1 which can't be rotated, and I'm not a fan anyway just like what BMW thinks.

Rotating can cause faster wear even though it evens them out, and belts can let go from doing it.

 

[40w8]

I noticed you said you'll get new tires in spring. This cool time of year is great time for them to cure without being heated a lot, yet.

I think Michelin even has $70/set off for a few more days.

 

[Quattro Pete]

Originally Posted By: 40w8
I noticed you said you'll get new tires in spring. This cool time of year is great time for them to cure without being heated a lot, yet.

I am up north. I am running winter tires now. I won't be putting the summers/all-seasons back on until April.

BTW, I just checked my records. My last alignment was 50K miles and 8 years ago.

 

[40w8]

I've sold thousands of tires, and that doesn' make me an expert because all kinds of rare things can happen.

However, the wear isn't on the edge like excess toe would cause.

I still think it's a loose belt not alignment.

You're about to fix it by changing tires anyway.

Just watch for wear on that spot of new tire.