I run 315/35/17 out back on my 99. I have no issues what so ever. Also I run 275/40/17 up front. I also run staggered 17x10 and 17x9. Even though you have 18's, the total overall diameter of tire and rim will be the same as my. 17's.
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2015 Race Red Performance Package GT 5.0 (435hp) stock
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