Biggest Tire In Stock Wheel Well?

DOT slick? street radial?
with the slick mabey a 28x10.. 9 is more like it.
radial 255 or 275/60/15. the 275 is a toss up, you may have to do some clearancing on the inside wheel lip
and depending how tight the leafs are, they may rub around hard coners.

yea a street radial. and this thing won't be taking hard corners ever! so a 275/60/15