Thanks Thimbiz, I didn't see that post before.

Is this going to be the case for all 17 Lexus rims? I was hoping to find a factory set of 17" that would bolt-on with no spacers, but with the proper snow tires, fill the wheel well as a stock 18" rim would (don't want the flush look or anything like that). I thought the IS lines might fit that bill, do you know if the GS ones will.

I going to go searching again. This offset thing drives me nuts.

 

Spacers can make this work, but just be sure you get meticulous balancing. I really like the RoadForce system. Those are nice rims.

 

I stopped by a tire shop this afternoon and found that the is300 rims I was looking at had the same offset as the stock SC430 rims. So, fitment shouldn't be a problem.

I called tirerack to see what size tire they recommend. They said that due to the weight of the car, they recommended a 17" rim (17x7.5-8) running 235/45/r17 tires. The rims I was looking at are 17x7 so he said those would need 225/55/r17 tires but was concerned it wouldn't clear my wheel wells.

So, I searched this form to see what others are running on their 17" snow tires. It looks like some Lexus dealers in Canada was selling a cold weather package that ran 235/55r16 tires. Am I correct that 235/55r16 and 235/55r17 tires are the same physical size other than the "cutout" for the rim? In other words, if a 235/55r16 works on this car, shouldn't a 235/55r17 tire work just as well (obvious difference of a 16inch rim vs a 17inch rim)?

Thanks again for all your help. I'm hoping to get this cleared up soon.

Brian

 

I have Michelin MXV4 225/55/17 on our SC430 and no clearance problems at all. I think the speedometer is off about 2 mph at 60. It reads 60 mph but we're really doing 62 mph.

 

I think if the aspect ratio is the same, the total diameter of the tire would have 2" difference. The speedometer will read lot differently. Go with thombiz suggestion.

 

I think it is off by 1 inch.