05-29-09, 02:39 AM
I have an 05 STS4 V8 1SG. The Premium Luxury Performance package includes 18' wheels with 255/45-18 on the back and 235/50-18 on the front. This struck me as funny as the front and rear tires are .8% different in overall diameter on an AWD car....but then I looked at a co-workers 2006 AWD with the factory 17's and noted that her car has matching tires (235/55-17, I think) at all four corners. Surely the transfer cases on our cars are the same, right? If so then has Cadillac built in the forgiveness of a small variance in tire sizes front/rear? I once had a tire guy tell me that I shouldn't buy just two tires for my AWD Honda Pilot if there was more than 2/32" difference in tread depth. I would like to put rims on mine but am scared to death of screwing something major up by either not staggering the new wheels/tires at all or not enough.....not sure what to do here. Any input would be appreciated.