:-\ I want to put a rear diff. that would help me get through the rocks, sand, mud, and what have you . The cruiser is a 1979 fj40 with 2f engine with a 4" leaf spring lift. Im on the pavement 80 % of the time. Can you experienced cruiser owners give me some advise. Im thinking Powertrax no slip positraction system, Auburn supergrip, Aussie locker,Lock-right . Thank you for any input