SCryder

will 235/45ZR17's fit the IS rim which is 215/45/17(i think)

Lexopolis

the IS comes with 215/45/17 on 7" wide wheels. The SportCross has 225/45's on the rear and uses a 7.5" rear wheel. Going to a 235 would require an even wider wheel because 5mm is about 1/4 inch and you want to go 10mm. The 235's will fit the stock 7" rim but the center of the tire will be pushed up like the edge of a donut. It is hard on the tire, not safe to drive on and will wear quickly. Do it right and get the proper width wheels.

SCryder

thank you for that info, the only reason y i ask and for the who are interested there is a set of 2 for sale in the wheel forum for $100 shipped with less then 500miles on them

Neo

iTrader: (3)

On top of the fitment, you would have increased the OD from 24.6 to 25.3. There will be minor speedometer/odometer discrepancies in addition to potential rubbing problems.

mmarshall

Since you have the same height / width ratio (45) on a wider tire, the height will be slightly larger....maybe enough for the speedometer and odometer to be off somewhat. This will not only give you potential rubbing problems but may affect warranty coverage as well. I'd stick with the stock wheels and tires.