I am looking at getting a LSD to put in my 2004 Hemi. I do not know much about the axles in these trucks. I know that I want to go with an Auburn Gear but I do not know which one I need. My truck has 3.92 hears but I have no idea which differential to get. Also, I have seen ECTED which is a switch that changes from a normal LSD to a locker in the back. Anybody running this?

 

welli'm 99.9% sure you already have a LSD...(pretty sure it's STD with the 3.92) but i wouldnt get the Auburn if you want to run synthetic fluid....some people have said that Auburn says it will eventually burn up the diff....i have the Auburn LSD and i'm using synthetic for various reasons.....if you want to run a synthetic then i would recommend getting the Detroit Tru-Trac.....i'd also look at getting a bigger diff cover...more fluid is always a good thing and helps keep temps down....Mag-Hytec makes a really nice cover, which is what i have on mine

 

Detroit also voids their warranty if you run a synthetic, or so I've been told by someone who has one and emailed them on the subject. So it really doesn't matter which you get. Heard nothing but good things about both. I have the Auburn, works great.
And you don't automatically have stock LSD if you have 3.92's. My truck is a 4x4 and came stock with an open diff. (thank god). My neighbor's '06 4x2 has 3.92's and an open diff., it's strictly up to the dealer to spec LSD when it's ordered.

 

Im not positive here but if i am recalling correctly, the 3.92's came with the lsd IF its the big horn edition or specifically ordered...

 

thats very possible...like I said, i wasnt 100% sure but every truck i've seen with the 3.92 has had the LSD....so who knows lol.....i'm gonna make my own LSD and say that it has to use synthetic and I will void the warranty if you dont lol

 

Thanks for the info guys! I am pretty sure that my truck does not have a ls in it. I'm still about a week out from buying it so I'm going to do a little more research. I have to get the rear end locked up before I go and get the STS kit which is coming in about 3 weeks. I just got back from the desert and have some money eating a whole in the pocket, lol.

 

All Big Horns? Because my 08 got stuck yesterday and it was 1 wheel in front and 1 in back.. Kind of sad that a 4x4 isn't just that.

 

My truck is an 04 and am with 20s and stock LSD. I later pulled it out, sold it and installed an Auburn LSD, went with Motive 456s and 36" tires and Royal Purple differential oil (75-140)