Rear tire wear pattern - is slightly uneven more normal than even?
 

Recently while I had all four wheels removed for checking brake pad wear I also checked, for the first time, the tire tread wear on a set of GSD3s that had a little over 13K mi. on them. I have no particular question about the front tire wear pattern - it is pretty even across the entire face of both tires. Some minor cupping on the sides - no big deal. It is the rear tires that I have a question about. The left rear, on the first inside groove, is now 6/32nds deep, and the outside groove is 8/32nds (original depth 10/32). The right rear tire is almost a perfect 7/32nds across the entire face of the tire. The inside groove is maybe 1/64 less than the outside at the most. Both rear tires on our C3 have always wore more like the C5's left rear - not very even. On a C5, would you say uneven rear tire wear is more normal or could it be that the nearly perfectly even wear pattern of the right rear is more normal? I'm just wondering which side is slightly off in camber? This car is used on the street only. I am mainly soliciting the first hand observations of C5 owners who have had considerable experience with tire wear patterns. Thanks.

Wow, does this mean that of all the veteran C5 owners none have an opinion on what constitutes a normal rear tire wear pattern?

Maybe the cause of this indifference is the fact that there is not much excitement or controversy involved in analyzing tread wear patterns?

I would think that you would want the suspension settings so that you get even tire wear for the way you drive the car.
If one side is wearing uniformly across the face, why would you think that uneven wear is normal??? I can see why you would have a question if both sides were wearing the same, and they were uneven, but not if one is even. I would say that is the "normal" one.
By the way, if you are running more than about -1/8 degree camber on the front, you will get noticeable inside tire wear from normal street driving. My Z06 came with almost a full degree negative camber from the factory (which is within specs), but I noticed inside wear within 1000 miles.

Rear end alignment
 

I recently had rear tires installed. The left rear tire had normal wear all the way across, but the right side was down to the steel belts in an area about 1" wide at the far inside of the tire. The tire shop guy said that it was an alignment issue and that he could fix it. I have not had a chance to take him the car, but will soon. Makes sense, since the rear suspension is independent. anyone else out there have a similar experience?

Get an alignment, but make sure you are in the Vette wehn they do it. Your body weight will effect the camber. The camber adjustment bolts can loose and allow it to change.

All four of my tires wear evenly in terms of left and right sides of the tire.

The rears of course get bald alot faster than the front. :D

Both of my rear tires are wearing evenly across their width at some 20,000 miles.

My only experience with an IRS is the '73 coupe which we've had since it arrived in '73. It has always exhibited slightly faster wear toward the inside on the rear tires. I was always told it was normal and due to IRS camber. When I noticed the C5, which we've only had for a year, wearing evenly on one side but more like the '73 on the other, it got me to wondering. Thanks to all for the comments! It sounds like it may be normal to have more even rear tire on C5 - interesting and of course more preferable. Now I know which side needs adjustment.

PM Evil-Twin, the retired GM engineer. He should be able to give you a good answer.

All the C5's (and C4's) I have observed and discussed tend to wear the rear tires in the middle section very quickly, with no discernable wear out on edges. This indicates to me that these cars have good alignment, and a driver who likes to use the power occasionally. Typical wear life for the center of the tread is 90% at 18-20k miles, with the edges of the tread looking almost new. I personally have tried various air pressures to reduce the center wear, but no luck; if you use the Vette's torque as it should be enjoyed, you WILL wear the rubber off the center section. Uneven edge wear on either tire would indicate an alignment issue, or serious track usage (again another good thing!).

Also, the fronts, as mentioned above, tend to wear the inside edge, especially the right front tire.

DG

13K miles on performance tires is just about too much

Tread depth has little to do with grip or performance

Tread wear has more to do with alignment.

Even tread ware across the tire may look and sound like a good idea and will make the tires last longer, but not really the best for handling and performance. So there are trade offs

I did PM Evil-Twin and we had a good discussion on the subject of proper rear tire wear pattern. The bottom line, sort of paraphrasing him, is that the rear tires will wear evenly if the camber is set absolutely perfect to factory spec with no error whatsoever, not even the normally allowed + or - region, But the big problem is that it is extremely difficult to locate anyone proficient and patient enough to do this. :ack: