I don't think so. I can't find where it might be in the warranty language. I noticed uneven tread wear on mine at 20k. When I had it aligned the shop owner said it is very common for the GM trucks to come off the line not properly aligned. I had him true the wheels as well. There was a noticeable improvement in ride after that.
I have had the same problem with tires being out of alignment since day one. Now with 35K on tires being rotated every 7K, the toe-in is way out on these 17" tires and they are almost 3/4 gone in wear b/c of this. and yes I was also told that this is a common GM problem with their products.....and so it goes....I guess I'll be out over 100.00 for an alignment...and then tires will have to be replaced and their goes another 1000.00 or more......
I had this problem on the front two wheels of my Ext. At 35k miles the inside of the two front wheels were almost bald with wire sticking out. It was my fault that only the front two got that way since I didn't get the tires rotated regularly but at least the uneven wear was only on two tires. The tech at Cadillac said that I should "flip" the tires so the inside part is on the outside and get an alignment every 15k miles since this is a known defect from GM trucks.
They will stand behind it if you report the problem early, this happened to a Suburban I owned, that pulled real bad from day one, they aligned it several times and even replaced the tires on the front end at 15k miles.