2006 GS AWD. Just hit 20K. How do I know if I really need to replace with runflats? Do I just check with a tire gauge? How much tread should be left?

Is there any harm in changing to convensional tires?

 

Be extremenly vigilant on your front end alignment checks and also a detailed inspect of the ENTIRE tire tread including the inner 0.5 inches. I had my GS430 with only 18500 miles and was running on the white cord without my knowledge. I had the car serviced by Lexus including the annual state inspection at 14500 with no issues noted, and 3000 miles later I had worn down the inner tread on one tire. The only way I found the problem was the low pressure light because one of the tires lost pressure and the excessive wera was not noticeable unless the car was up on a lift. Sticking your nose to the ground just wasnot good enough for these very wide tires. A check of all 4 tires on a lift revealed all 4 tires worn on the inner side with one of them showing the white cord (I was lucky!!). The Lexus dealer says the GS 430 is especially prone to getting out of alignment which in turns wears out the run flats quickly.

Bottom line, I replaced all 4 with non-run flats and it was the best thing I ever did. I also bought the spare tire option for $180.00 They run quieter with better handling and better tire wear characteristics.

 

Which tires did you replace it with? Also, what is a "spare tire option" and what do you get for $180, a donut spare without a rubber or what? I think neither GS430 nor GS300/350 can fit a full size spare in the trunk, just a spare donut wheel.

 

I had Lexus special order me the spare tire option, which includes a rim and a donut tire (temp spare). Allowed me to go the non-run flat route.

As to non run flats-there are many tires made in the GS 18inch tire size. I think they run $150-225 based on your desires-check www.tirerack.com. The price is very dependent on the speed rating and tire brand. I even saw some Nexen's for $99-which is a great handling tire but it is a Korean knockoff

 

Nice to know this rim/donut spare cost $180. I'm gonna use that as a reference when talking to my dealer. BTW, which Lexus in PA did you get it from?

Regarding run flats, of course I'm aware of tirerack site. I was just hoping to find out which tires you picked and your experience with it. Basically, would you recommend it to others? I know PA roads can get as bad as Jersey, I used to live in Harrisburg