I have a stock 2001 GMC z71, can I run 20" rims on it & if so what's the largest tire size I can use without needing a lift kit??
Yes you can run 20" wheels. As far as tires I would talk to a tire store or got to tire rack.com. They have a great feature on their website that allows you to see your truck with 20's on it and will give you tires sizes that will fit. This increase in wheel/tire size will change the speedometer in your truck.
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