I heard the 17 inch rims on my is350 are the same size all around but the tires are 225 in the front and 245s in the back. Will 245s all round be ok? Why didnt they just use same size tires so we could rotate them, pretty stupid if you ask me, whats the point?

 

Cuz staggered wheels is JDM yo!

 

Yes 17" stock is 17x8.0 all around using staggered tires for RWD.

245, front, probably not, going to rub and also may affect the odo. The other thing is, the car is going to look funny, and look more like a AWD with 4 tires the same size.

Unless, you're going up to stock 18" specs, then it's 18x8.0 front on 225/40/8, 18x8.5 rear on 255/40/18.

 

Its hard to tell the difference of 20mm, but I didnt think a 245 tire in the front would rub.

 

what about traction control. and abs sensor , there is about 3.5% of tire size difference , oem size are 225-40-18 and 245-40-18 on the sport model . ive called just about every lexus dealer and no one could tell me exactly if it would be ok. im looking to buy winter tires and ive got a super deal on 4 18 inch tires. same size.

 

I run 205/50R17's all around during the winter and 245/40R17 all around during the summer.

Not all models came with staggered tires, base model RWD IS250's came with 205/55R16's all around, and as far as I can tell there are no differences in any of the computers between models that have the staggered and non-staggered setups. RWD IS350's always had staggered.

Jeff