This is on my S4.

This is my left, rear tire. The wear is on the inside of the tire.

As you can see, it is pretty well worn through, while the rest of the tire has some tread left.

The other picture is of the inside of the wheel well. There is a pattern of wear on directly next to the inside, top of the wheel, on the wheel well. There are no marks on the top of the wheel well, or the inner fender.

What could be causing this?

I'll head in and get new tires later today, but I want to know the cause of this before I ruin another tire.

Thanks in advance.

 

Looks as if the left rear wheel is out of alignment. Excessive wear on the inside of the tire suggest a “toe out”. The wear on the wheel well isn’t severe enough to cause the tire to wear out like that. If that was the cause the undercoating and paint would be worn off. I think it only contact the wheel well on occasion, such as hard cornering or a large and sudden dip in the road.

Perhaps the left rear wheel hit a curb at some point and was either knocked out of alignment or something is bent in the left rear suspension.

 

Excessive camber? You don't mention size or offset.... if it's a "standard" size then it shouldn't rub except due to excessive camber, caused by loose bushings, bent components, etc.

 

Brett,
It may help if you would add the tire size, wheel specs ( or just 'standard 8x16 S4 rear') and suspension heights. Are rear shocks Ok - and dry? The rear adjustments are toe and camber: camber is easy to eyeball left to right using a 2' level vertically over the centerline; however, such wear is frequently 'toe'.
First impression, I'd confirm suspension heights and plan on an alignment prior to running on new rubber.

 

Another question is if you could feel vibrations through the body at any speeds. If this is an alignment or wheel balance issue, I would guess that you should feel it as the tire appears to not be wearing out uniformly on the inside. It appears that there are patches that are wore out worse than other areas on the same line of travel. If it is alignment or wheel balance related, you should have felt it at different speeds and given how extreme it is, I would suggest you should have felt it at non-excessive speeds.
If you felt the vibration, could be alignment related (camber, toe) or wheel balance related - bent wheel. You may want to get your tire shop to do a balance check on the old one if you want to confirm that the wheel balance is okay.

 

Toe, in my experience camber wears one shoulder more than the other, but the wear is even around the tires. (996s are famous for camber wear on the rear tires.....I finally had to adjust the camber myself, cause the spec is too severe for long distance driving)

 

I have 245/45/16's on standard s4 wheels. The ride height is standard and shocks look and feel ok.

The rim looks like it's been curbed a few times, maybe hard enough to jack the alignment.

I get an alignment along with tires then.

Thanks for the help.

 

You know it needs to be a Hunter DSP400 rack, right? And under no circumstances are they to lift the car! If you put the new tires on 1st, drive it for 25-50 miles first to settle the suspension then go in for the alignment.

 

That 'scalloped' pattern is usually an indication of a worn-out shock. That could easily translate into scrubbing as the camber changes. So, verify that the shocks are OK, recheck the ride height, then the alignment.

Besides the normal "don't lift the car!" warnings about alignment, work with your alignment guy so you either sit in the driver's seat while he does it, including the ride height check, or get a few bags of sand for the driver's seat.

Show the alignment dude the old tire before you do the new alignment. An experienced alignment guy will take the clues from the tire and use them to help him focus on what needs what under the car. Take advantage of his knowledge.

 

Well, nobody in the area had 245/45/16 in stock. Can anybody get me a good deal on a set?

I did have them do an alignment check while I was there. Can someone interpret these results for me?

LF
Camber -.3
Caster 4.6
Toe .29

Front Total Toe .42 Steer Ahead .03

RF
Camber .1
Caster 4.1
Toe .23

LR
Camber -1.6
Toe .14

RR
Camber -1.4
Toe .36


Rear Total Toe .50 Thrust Angle -.11

Looks like negative camber has both rear tires leaning way in at the top.

By their calculations, everything is out, some way out, except left rear toe. They could only check the alignment anyway, since they didn't have the drawn bar(?) to do it correcly.


Look through the huge stack of receipts the PO gave me, I see the last 4-wheel alignment being in September of 2002, but only 5k miles ago.

I also found the original window sticker in there . $81, 132 in . Wow! I think that's like $140k today.




Thanks for all the help.

 

If the front of your car was lifted by the Tech to check ball joints, calibrate his machine or whatever - these readings are meaningless ( you noted the absence of a draw bar - which is only req'd if the front had been lifted).
The correct ranges ( from the program in a Hunter DSP 400) are
front camber -.67 to -.33 front caster 3.5 to 4.0 front toe 0.08 to 0 17
These are all in degrees, and note that S4 caster can rarely be set lower than 4.0 - simply minimize one side and crank the other to match. A 4.5 is more typical. Therefore, if your car had not been lifted, left camber is close but the right is positive ( tilts out at the top). Caster is OK, and front toe is cranked in a bit much.
For the rear, caster [edit - read 'camber'] spec is -.83 to -. 50: Your caster [edit - read 'camber'] is tilted in at the top twice the spec! Rear toe range is 0.08 to 0.25. A little too much on the right.

The rear camber is set to wear the inside rib off .... and camber in the front is pretty asymmetric.

 

Garth, might want to look that post over and see if maybe you're using "caster" where you mean "camber"...

 

Good catch! I slipped in the second last sentence re the rear - all is correct concerning the front suspension, and in the last sentence dealing with the rear ...spell check apparently cannot catch everything, like operator error ...
Will now hit 'edit' ...