Bill Ball

I drained the diff fluid again today after another 100 miles and it looked clearer and there were no more metal filings on the drain plug magnet. I replaced the Redline 75/90NS with Mobil 1 LS. IMMEDIATELY the shuddering was gone. I don't know for sure if that is a good thing, but it no longer shudders on parking lot maneuvers. If I had a little more horsepower, I'd do a burnout and see if I get 2 stripes.

sgschroeder

My 2 cent's worth-
Redline 75/90 NS is NOT the proper choice for an LSD!!! Either use 75/90(NO NS) or add Redline friction modifier. 75/90 NS has additives to enhance old LSD's friction Co-Ef and/or help older synchros. It is typically used in open-diff transaxles that share the same lubricant.

Bill Ball

You are quite right. So, the Redline response to James was incorrect. It's even clear from the bottle label information that we should be using 75/90 without the NS designation.

NoVector

Would the same be true for systems with a PSD?

SteveG

This was never answered. I will PM Gregg just to be sure.
[Later] Gregg says he knows of no other "requirements" for the PSD, so his earlier recommendation stands.

Bill Ball

I would think so. Redline 75/90 or Mobil 1 LS seem to work, and I would not use Redline 75/90 NS, at least in an automatic. I think the variable that may alter this is whether you are talking manual or automatic. As I recall Greg really likes Mobil 1 LS whether auto or stick, and didn't have a lot good to say about Redline. I have M1 in now and everything seems pretty good. ' should check the magnetic drain soon and see if there is any new metal.

Speedtoys

I had M1 with my new tranny....noisy as heck.


I replaced with LSD safe Redline...nice & quiet.



I drive an Auto.

Bill Ball

As long as it's not Redline NS, right, Jeff?

Dan87951

Anyone know about how much replacement friction disks are for late LSD's?

Bill, good to here a fluid change got you fixed up.