i plan on keeping the rims that are currently on there, im not quite sure of the size, but the tires on there now are 265/70/17. im looking to put some mud terrain tires on there and get a wider stance on the truck. i am planning on putting 3/4" or 1" spacers and i would like to know the largest tire that i can use with these rims.

thanks

 

you can go up to a 305/75 or a 33"x12.5" on the stock 17x7.5 rim. that is what i run. not sure if anyone is running a 35" on stock rims.

 

You can easily fit a 285/70-17 (33x11.50) or a 33x12.50-17 on your truck using the stock wheel. Another option would be the 305/70-17 (34x12.50) Goodyear Wrangler MTR. A few people have fit 315/70-17 (35x12.50) BFG AT KO's on stock 4x4's by using the stock 17x7.5 inch wheels and cranking up the torsion bars. The 35's are an extremely tight fit however and you will probably have some minor rubbing.
Also, I would advise against using wheel spacers. They produce increased leverage and wear on steering and suspension components and will cause problems with tire fitment.