Almost 80,000 Miles on a set of tires.

I just replaced a set of Michelin LTX-AT2 in load range 'E' on my truck that had 45K miles on and were 3.5 years old. They still had 11/32 tread depth, which would mean my Tundra would go nearly 100K miles on the tires. The sidewalls were cracking nasty. I never put anything on the tire like "shine", etc, but the truck does sit out most of the time in Vegas sun/heat. I bought the tires at Discount Tire, and they took them back under the Michelin warranty and gave me nearly what I paid for them towards another set of tires. I decided to go with another set and see what happens, mainly because they ride great and wear well, if the sidewalls hold up these will be the last tires I ever buy.