I can't make up my mind if I want to regear (4x4 on 33's, but more for performance reasons) to 4.10 or 4.56, but if I do I plan on adding a Ford Racing LS unit. Is this the OEM style LS that comes in all F-150 LS differentials or is this a "beefed up" unit? I say I want to go with a LS unit because they are $200 compared to $500 and I don't do any serious offroading. I also haven't had that much of a prob. out of the open diff.

I just don't want something that's going to be near worthless if I do need it and I don't want to install another wear item in the truck unless I can get almost 100,000 mi. out of it. TIA!!!

 

If you plan on staying with 33s then 4.10s are the way to go. With 4.56s you would pretty much be limited to city driving. Anything over probably 60mph you would be running at excessively high rpms. I just ordered 4.56s for my truck today and I'm on 33s also. The only reason I bought 4.56s is because I don't do any highway driving and I'll be stepping up to 35s as soon as I need new tires.

I don't know.

As I have said before, the Ford LS <i>is</i> worthless. I used to have an open 8.8, but when I blew it I replaced it with a factory Ford LS. I am constantly dissapointed with it. You said that you don't do much off roading, so it's not likely that you'd ever really notice how pathetic it is. I understand that you just want something better than an open rearend, because I did the same thing. I now wish that I would have just spent an extra $100 and got something else. As far as getting 100k out of it, you'll probably have to get the clutch packs replaced before then.

 

Hey guys ive got a 99 f150 2wd with a limited slip and im thinking about getting the fluid changed on it because i have put on 113,000 miles on it and i do off road with friends on the weekends. If i do need a new clutch pack, how much will that cost? Thanks for the help.

 

Alright, I'm convinced...but are there any bomb-proof LS units out there without going straight locker?

 

I'm sure there are, but I'm not the one to talk to about that. I just speak from experience and I don't have any experience with aftermarket rearends. Whatever you decide on, I'm sure you'll be happier with it than I am with my Ford LS.