Does anyone know what 17 's will fit in place of the 18's so I can get 4 matching tires and rims

 

Funny, I was just replying to another thread asking about smaller wheels.

You should be able to fit OE 17-inch 2nd-gen IS wheels on it.
See:
https://www.clublexus.com/forums/is-...l#post11658374

Or, if you get the right offset, you should be able to find aftermarket options as well, but I don't know of anyone running aftermarket 17's offhand.

 

I run 17” wheels, in a square setup, in the winter on my 2014 IS 350. Got the wheels, and winter tires, from TireRack.

 

Go to TireRack.com, plug in your vehicle details, select wheels, and you’ll see lots of 17” wheel choices.