I have an 08 is350 and im running 225/40/18 up front (18x8) and 255/35/18 in the rear (18x8.5)

i was wondering if i can do 235/35/18 up front and 265/35/18 in the rears.

Yes you can, I got that same size put on by the dealership I got my car from, because the rear tires were gone ( I wonder why haha)

That tire was on stock Lobster claw wheel same as yours 8.5" wide

My car is also lowered on F sport springs

Welcome to Club Lexus

I'm lowered some and running 235/275 with aftermarket rims without problems.

yep 235/265s will fit with not much problems.

keep in mind not all tire sizing is created equal or run true to size.
in other words a 235/35/18 Michelin may have a slightly different sized sidewall than a 235/35/18 Hankook.
this may only matter if you only have millimeter of clearance but it's unlikely since 265 is not too wide.

275 on 8.5 width? if thats safe then i will most likely go that route. unless its a bit risky i would stick with my 265s on 18x8.5

You can safely do 245/35/18 tires up front on stock 18x8.0 wheels (I had that setup in the past).

265 tires on an 18x8.5 wheel is not recommended but you might be able to get away with it (at risk).

Old pic, and not that good for showing fitment, but those are the 265/35/18's on the stock 18" lobster claw wheels

For what its worth, I had no issues running those tires..

okay i guess ill just stick with the 265s.

thanks guys

You need to check what the recommended rim width is for the tires you want to run. 275s may or may not be recommended depending on the tire, its pretty easy to check that on tirerack.com

does anyone have pics of wider tire setups on stock rims? like maybe 235 or 245 on front and 265 or 275 on rear?

Do u guys think I could use 22inch 265 width tires? All around