Alloy Wheel Sizes

[Dean8788]

Hi, I'm looking to change my alloys to some 18's. Do the rear alloys need to be a different size to accommodate a wider tyre?

[ColinBarber]

If you want wider tyres then yes you should ideally have wider rims so the tyres are square rather than pushed in or spread out at the rim.

The OEM 18" wheels are 18x8 on the front and 18x8.5 on the rear.

Tyres are 225/40/18 and 245/40/18. Not a great combination IMO as the rears have a larger circumference so the vehicle doesn't sit completely level. Thankfully Lexus went with 255/35 on the rear of the current generation IS which is much closer to the front circumference.

[BillNick]

Whats the ride like on a 40 or even 35 profile?

[normski2]

I have 18" and 40 profiles.

Ride is just right for me. Not too hard and not too soft.