I have set of C5 rims (polished thin 5-spoke) that I want to put on my 02 Trans Am. The rears are 18x9.5 with 275/40/18's and will not fit. The tires bind up against the inner wheelhouse but it looks like a spacer may take care of the problem. I'm not sure what size spacer to try.
Does anyone else have this set up and have a good answer to correct the problem? Thanks

 

Are they OEM C5 18x9.5" wheels, with a 65mm offset? If so, they will sit very deep in the wheel well, but should not be putting the inner edge of the tire against the inner fender liner. That's a 7.75" backspace, and many of us don't get into trouble until backspace approaches 8.0". Is it rubbing on both sides (driver and passenger), or only on one side? Rubbing on one side would indicate a problem with the panhard bar.

If its rubbing on both sides, its an odd setup, and about the only way you will be able to get a spacer size would be to stack washers on at least three of the studs and test fit the wheels until the washer stack is thick enough to keep the tire off the body. Then measure the thickness of the washer stack.

 

They are OEM wheels. I tried the L/R first, saw I was in trouble and stopped. I'll measure, try the R/R and see how it goes. Thanks for the reply.

 

I used an 8 or 9mm spacer for my OEM 18X9.5 C5s and longer wheel studs for the rears.

 

1" bolt on hub spacers like eibach or h&r will give you a +39.6 offset (that is if the offset on those wheels is + 65mm) and are a lot safer than slip on spacers , but you might need to roll the rear fender lips a little. You can get them online for around $150.