Change your rear diff oil if you haven't yet and clean those lockers!

[DParenti547]

Looks like AMSOIL has 75w-85 now.
I wonder if Banks will still recommend AMSOIL 75w-90...

 

[Lynaugh]

Looks like AMSOIL has 75w-85 now.
I wonder if Banks will still recommend AMSOIL 75w-90...

Sorry to resurrect an old thread and please excuse my ignorance haha
I was looking to change the fluid in the transfer case and front/rear diff this weekend and have been trying to do a bit of research before so. I see that almost everyone says they use 75w-90 in the diffs with no LS additives but from what I see, the OM and Amsoil recommends 75w-85 w/ additives. Just making sure I get the correct fluid. (for a 21 PW) Thanks!

 

[HEMIMANN]

What axle do you have?

 

[Lynaugh]

What axle do you have?

I don't know specifically but when I search the VIN I get AAM 9.25 front and 11.5 rear, 4.10 gearing

 

[HEMIMANN]

If you have 11.5" dia. rear ring gear, the only manufacturer I'm aware of is AAM. If it had Trac-Rite all gear torsen differential, then it does not need LS additive as the manual says. It is beneficial not to have LS additive because it slows torsen gear lockup when a wheel is spinning.

The only axle gear lubes I found were MOPAR 75W-85, Red Line NS 75W-90, and Mobil Delvac 1 75W-90, which is what I use in mine.

 

[Lynaugh]

I see, I guess the owners manual and the vehicle look up (like on Amsoil's website) are pretty generic as you can only search year, make/model and engine, but I do appreciate the help, thank you!

 

[joesstripclub]

If you have 11.5" dia. rear ring gear, the only manufacturer I'm aware of is AAM. If it had Trac-Rite all gear torsen differential, then it does not need LS additive as the manual says. It is beneficial not to have LS additive because it slows torsen gear lockup when a wheel is spinning.

The only axle gear lubes I found were MOPAR 75W-85, Red Line NS 75W-90, and Mobil Delvac 1 75W-90, which is what I use in mine.

I see, I guess the owners manual and the vehicle look up (like on Amsoil's website) are pretty generic as you can only search year, make/model and engine, but I do appreciate the help, thank you!

I went with Mobil Delvac as I needed non-additive gear lube for my car as well. Summit racing had a good price and I think you got free shipping at 3 bottles at the time.

There is also Castrol Syntrax but its a little more expensive and harder to find.

 

[HEMIMANN]

I called Amsoil and talked to their Rep. This was several years ago. He said all their axle gear oil contains LS additive.

I also called Mobil and they said Delvac has no LS additive. Red Line website says their NS gear oil has no LS additive.