I bought my 2005 GP a month and a half ago. 20k on it, appears to be original tires. Well, since I picked it up from the dealer, I can hear a slight road noise. It was getting difficult to ignore. So I took it to my tire shop, the guys there are good friends and excellent businessmen. The guy's immediate reaction was that you have a blister on the outer edge. He showed me where it was cracking, he said basically the belt inside is giving away. He walked around and looked at the other side and found one even worse. He thought if he took the other tires off, it's likely he would probably find all four of them have the same issue. He said this is common for these Goodyear tires they put on from the factory. They are a 40k tire, these have 20k on them and they're half worn, 5/32. A new set of these factory POS Goodyears are $520 roughly. A new set of Michilen Harmonys are $560, and a set of Uniroyal Tiger Paws are $395.
I'm going to take it back to the dealer and talk to the service manager. I'm not happy about this.
Why would GM put these crappy things on from the factory? They're an expensive 40k tire. Michilens are 80k tires for about $10 more/tire, and the Uniroyals are also 80k for much less money!!!