I have a 2010 IS350, which I ordered new tires for from Tire Rack. I had them shipped to a local NTB and put on about a month ago. One of my wheels with a small nick in it was previously at the driver's side rear location. Just noticed the other day that this wheel is now on my passenger side front.

I have the OE 18" wheels, staggered setup for RWD. Is it a bad idea to have the 0.5" wider wheel(s) on the front with the 225/40/18 tires?

 

Maybe, they just made another nick of the front wheel's? I don't the rear 8.5 50+ offset fit in the front? I could be wrong

 

I've thoroughly inspected both rear wheels and can't find the same chip that's on the passenger front. They're powder coated and nick/chip I'm referring to looks like a rock it the wheel and knocked all coating off, so it's silver in that spot.

Probably going to call them up tomorrow and take it in to have them confirm. Did notice the car felt a bit weird after I had the tires put on, but just assumed it was the difference of new tires vs. old worn out tires. For all I know, both front wheels could be the 8.5" size.

 

Any tire shop will have a wheel measuring caliper that they use with the balancing machines, so they should be able to check in a matter of seconds. (I would think you'd also be able to tell just by looking at the sidewall of the tire, 225 tires on 8.5" rims should look at bit stretched.) I would definitely have them check, and correct their work if they screwed up.