first i've read numerous posts on open vs. LS diffs. but i still cant figure out what i want, to go with the new gears im putin in. i have a 97 f150 4.6 with 3.55. i just put a 6" fabtech susp. lift on it with 17" rims and 35 tires. i do quite abit of offroadn not real strenous stuff but alot of gettn from here to there. i wanted to put 4.56 in it but was wonderin if that was a little overkill. and i still have no idea what to use for the diff. limted slip or open or an airlocker. and what for the front diff. im in the navy so the checkbook is not real deep but should get the job done. this is my do everything in truck and does alot of pavement pounding before it goes off road. just was lookin for some advise from someone with a little more expertise in this field than i've got. thanks for any advise ud be will to dish out. JJ

the only reason i ask this is the old trusty ford mechanic, my old man, told me id rip my tranny out if i didn't regear it. and with regearn it why not try to improve it.

 

Yeah for sure if your gonna spend the money for deep gearing and big tires, make em both work in the back. Limited slip or a locker will get the job done, but a lot of pavement pounding will favor limited slip.

Adrianspeeder

 

For a daily driver go with the limited slip. Personally, I would go with a Tru Trac limted slip (the same company who makes Detroit Lockers). Tru Tracs are 100% gears, no clutches, cones etc. to wear out and they use regular gear oil (no friction modifier to add).