Dealership service dept. should be able to give you this information.
It depends on the vehicle. I had a little clearence issue fitting 35's on my 94 F-250 before I lifted it. Its kind of a trial end error thing, but anyone at a tire shop could tell you.
most jeeps stock can handle 31 with minimal rubbing at full compression
I think the new Wrangler JK's can fit 32's stock.
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