I bought my 2006 RX 400h new. At a little over 12,000 miles, the original Continental tires were down to the wear replacement marks. I took it into our local dealer and made a fuss. They replaced them with Michelin tires that the new models had for free. Then at just over 25,000 miles the Michelin tires were down to the wear replacement marks. Sad. Out of Lexus original warranty by then. All Lexus dealer suggested was to contact Michelin direct.
I called Michelin and made another fuss with their customer service and they gave me a rebate number/case number to use when I purchase replacement tires. I shopped around and found a high rated Bridgestone with LRR, quiet, rated high in handling and performance and 65,000 miles warranty at America's Tire Center. Also got the free replacement warranty with it. With the special price sale, additional $80 rebate on a debit card and the Michelin adjustment that was given with the case number that America's Tire confirmed by phone, the total for the 4 new tires was $180 to me. Michelin no longer offered a mileage warranty for Lexus RX models. Strange.
A few weeks after I purchased the new tires, one of them developed a leak going down the road. AAA put the spare on and could find no reason for the leak. America's tire replace it for free because the low pressure had ruined the sidewall of the tire. America's tire could not find out what caused the leak either. That was worth the few bucks for the replacement coverage.
The RX mileage is at 50,000(25,000 on the Bridgestones) and they have plenty of tread left. Probably another 25,000+ mileage. I am happy. Why in the world would Lexus put us RX owners through the hassle, though?
CDFCHIEF