I have a 2000 f 150 sc 4by and want to know how big of tires I can put on after I level my truck by cranking my torsion bar on the front

 

Welcome to the site Ozzie! The largest tire you can fit on your stock truck (with minor trimming and/or cranking the torsion bars is a 305/70-16 (33x12.50-16) on a 16x10 inch rim. Or if you perfer a larger rim, a 305/70-17 on a 17x10 inch rim would be the same height and width.