Question Rear Axle Servicing

[Don Johnson]

I've changed the oil in mine, but I have to be sure that there is NO FRICTION MODIFIER in it because I have a True Torque diff in it and the instructions say to NOT USE a friction modifier. I'm thinking that the guy that installed it (supposedly a "professional") used the regular stuff he puts in diffs and that just may have hurt the diff's ability to operate the way it was meant to as I have done the sort of tests the manufacturer recommends and it just doesn't see to do what I think it should do, which is to route the available torque to the wheel with the best traction. I'm hoping that by changing the diff oil more frequently that needed will sorta "wash away" the stuff that may have contained friction modifier.. What do you all think??

 

[DaveBen]

I would remove the current oil and add regular diff oil. Drive it for a little ways (50 miles or so) and change it again. This should get any friction modifiers out. You should be GTG. [Good To Go]

 

[Kleetus]

You could also change the fluid and spray down the center section, particularly the clutch area with carb, brake cleaner, or diesel, to hasten the release of material in the modifier. That stuff will be in the tubes and everywhere else. Friction modifier only makes the clutches slip smoothly so you don't get chatter... unfortunately the lack of chatter also means they are slipping instead of grabbing, which is literally the opposite of what you want.

 

[DaveBen]

"unfortunately the lack of chatter also means they are slipping instead of grabbing, which is literally the opposite of what you want." Not entirely true. Think about a clutch. You don't want the clutch to chatter. You want it to be smooth when you disengage it and engage it. The clutch will still grab with enough friction to make the driveline work properly. Chatter will cause transmission problems/failures, down the road. If the clutch slips it will quit working very soon.