I have an 05 Z51 MN6. I almost have 17K on the car. The center of my rear tires is wearing alot faster than outer edges. I constantly run 30 psi cold in all 4 tires. The fronts are perfect. The next set should I run more or less psi in the rear?

 

Sure sounds like it.

 

From what you explained, it sounds like you are running to much air pressure in the tires. Have you checked with a tire guage or are you using the info center? Do you run this car alot on the track where you could be really heating up the tires for an extended period of time? This would also cause tire air pressure to increase during that time frame. Just something to think about

 

All else being equal, less.

 

At 8000 miles the center of my rears have worn 1/32 more than the edges. I have always keep 30 pounds in them. I lowered them to 29 and will monitor the ware.

 

I would think you need to run less pressure, but I believe I read somewhere that, counterintuitively, the center wearing faster is actually caused by too low pressure, so more is needed. Bottom line: I am no help whatsoever, just wasting electrons here.

 

Wider tires run at lower pressures will wear in the center. I have always run with lower pressure (26 pounds) in the rears of my Mustangs and have the same wear pattern. So if you want less wear and unfortunately less traction (if you drag race) then run with more pressure (not a bad idea in the summer as the hotter air temps will reduce horse power anyway).

 

This is a response I got in the tire section...


"sallen619, a Forum member, Evil Twin, is a retired GM engineer and C-5 owner. He recommends running Corvette tires at 30 psi "warmed up" to prevent excessive center wear. I have tried that method and it works for me. The 30 psi setting cold, as he explains, doesn't work if you consider that pulling out of your cool garage into a 85-90 degree outside air and running along can easily produce tire pressures in the 34 -36 psi range and the results are predictable. Many folks running the 30 psi cold end up with excessive center wear. I average my cold pressures to "warm up" to a nominal value that does not exceed 31 psi "warmed up". I put 12,000 miles on a set of Michelin Pilot Sports using his method and got perfectly even wear and right now measure 6.5 to 7 32nd after starting at approximately 9.5 to 10 32nd. Hope this helps try to answer your question.

There are always opposing views, his method works for me. I live in the Pittsburgh PA area. In the summer, my cold pressures average 26-27. Once you get them set for the season, it is no more trouble than having to maintain 30 cold. Simply a matter of watching how your tires react to your driving style and outside conditions and adjusting the cold pressures to compensate for your average warm up temp."

 

I am sure willing to give it a go and try lowering my cold pressure. I replaced mine at 9K with tread bars starting to party.
I can use them for a heat cycle or two on the track. I have religiously had them pegged at 30 cold and basically like the tire but not the treadlife. My rear tires exhibited the same wear as you folks describe. I like the idea of run flats and for the time being will stick with them. Thanks for your advice.