Engine/Transmission (1994 - 1998) rear chatter

[dodge cummins]

i recently changed fluid in rear. it is a 4. 10 limited slip. i filled it with synthetic 75w140 and 8 oz of additive. since then it chatters on turns. i added more additive about 5oz and it chatters just as much. any suggestions?

 

[98slushbox]

I never ran any posi lube additive in mine, but its just limited slip. Does yours ever open up at all? may be grabbing too much with the additive. May have to try it without the additive. Just an observation.

 

[TRCM]

Limited slip & posi are the same thing... . the only difference if what brand truck it is in.



Both of them need the additive. You may need more additive, since the 8 oz bottle is the correct amount for a normal diff. A normal diff holds 2 qts..... the d70 hold 4 and the d80 holds 5.



If it has been driven a long time with old oil , the plates may be varnished. If so, it will take a while and probably a short cycle fluid change to clean them.

 

[dodge cummins]

maybe i should drain the rear and just put the the 75w140 in without the additive? any thoughts?

 

[K5IP]

There is a big difference in additives. Get the right stuff, from Dodge.

Rog

 

[Texasrattler]

All the references I have seen say use no additives. The 11. 5 is like a Torson, it use gears no clutches.



Pete

 

[GAmes]

I use Royal Purple. The additives are in it, so nothing to add.

 

[98slushbox]

I believe i used a 75-90 syn. and no additive and it catches posi about half the time.

 

[Extreme1]

i recently changed fluid in rear. it is a 4. 10 limited slip. i filled it with synthetic 75w140 and 8 oz of additive. since then it chatters on turns. i added more additive about 5oz and it chatters just as much. any suggestions?

The Dodge additive is the best. Anything else won't be as effective. That being said, the first thing you need to do after adding the additive is find a nice big, empty parking lot and drive around in about a dozen figure 8's. This will work the new lube in between the plates and they should start to slip, not shudder. If you do that and it still shudders, add the Dodge addidve 1 oz at a time driving the figure 8's between each addition.



Don't worry about changing the lube. Adding the limited slip additive makes the clutches in the l/s unit slip. If you add too much it's like having "one wheel peel" - unlimited slip. If you do the figure 8's and it's OK, give it a couple thousand miles and see if the l/s is too slippery (no posi), then you'll have to start over.



After I installed the l/s in my truck I added no additive. After a couple thousand miles it started to shudder so I added 1 oz and it was fixed.



One other thing to help us help you, fill out the signature info so we know what year your rig is, there were a couple changes to the l/s pack during the 2nd gen run.

 

[TRCM]

My owners manual says to add it.



You can get the dodge additive, or you can get the same exact chemical compound from ford, but they sell it cheaper.

 

[98slushbox]

I forget the two names now of the dana 80's but i have the one with only two spider gears instead of four. I was gonna restack the clutches and steels but since i have this dana 80 i was told to just try changing the fluid. tried and didnt help

 

[Extreme1]

If your L/S is the original '94, you don't need to restack the plates. Dodge told Dana to change the torque rating of the L/S around '99 or '00. I got my L/S out of a '00 and the plates are stacked wrong. Restacking them is on the list of things to do but since I can do big, smokey burnouts spinning all 4 rear tires, it's a ways down the list.



The guy I got mine from took it out and installed a locker because he kept getting stuck in his pastures with his new truck. I disassembled the L/S and cleaned it before installing it (would have been real easy to restack the plates then but I didn't know they did what they did) and it still didn't work too well. It took about 2-3 thousand miles before I felt the rearend chattering. I added 1 oz of lube, did some figure 8's and drove it for a few days and it's been fine since.



The Mopar lube is slipperier than other brands. Try a search, each manufacturer makes their own brew and the Mopar stuff is real slippery. I have some GM L/S additive for my T/A, different color and different smell.

 

[Joe G.]

I use Valvoline in mine. No additive. It seems to work fine. No chatter on pavement. One side tears up the ground more than the other on dirt. If it's slick both wheels will spin.

 

[98slushbox]

I could deal with a little chatter if i could get it to stay locked when i need it to. My truck is light and I dont ever tow so i could deal with it.