I have a 2000 Dakota Sport, 4.7L, regular cab 5 speed manual. It has a 3.92 diff in it and the top of the housing is cracked. I found a used one that is 3.55. Would I be bale to get the one with the 3.55 and swap out my parts? Thanks.

 

Yep. Keep in mind though, that gear set-up is CRITICAL, and if you haven't done it before, having someone that has, help you, is pretty much a requirement. Doing it wrong can be anywhere from merely annoying, (loud gears) to downright dangerous. (gears blowing up while you are driving.....)

 

I talked to the garage I go to for stuff I can't handle and they weren't sure and won't do internals for diffs because of that reason. I'll just find one of the same ratio. First I'd like to see if it can be welded if I can find a good aluminum welder. It is cracked on the top (no idea how it cracked up there). I just bought the truck for my son recently and discovered the crack after. I initially thought it was just the seal on drivers side axle which was bad too. The garage put some JB weld on it to see if that would work an it doesn't leak much but would like to have it fixed either way. Thanks for the info.