Ok so right now I have my 255/75R17 and I am seriously considering getting some 315/70R17 BFG A/T's. To do this I would get either the Toytec ultimate lift combo or the Icon coilovers and icon springs out back. I already have a body lift so I should be ok. Here are the differences between the two tires:

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
315/70-17 8.7in 17.2in 34.4in 108.0in 587 0.0%
255/75-17 7.5in 16.0in 32.1in 100.7in 629 -6.7%

Well anyways my question is basically do you guys think that these tires would fit on the stock 17" rim? I am sure it would fit but it would probably be better off on a 17X9" rim or something.

Ideally, 17x8 with zero offset. Check the approved wheel width with the tire mfr. Also, you'll need to research what it takes to fit 35's. Chopping the front body mounts is needed to prevent rubbing.

Search here for member ALEXJET,He has fitted 35's on his rig.I think it would safer to go with a 17x8's to accommodate the 315s but alex if i remember is using procomp 17x9' rims. http://www.toyota-4runner.org/showth...threadid=31451

jst remembered theres a thread on toyota120 called 35's on a 4runner.. lost of good info over there