RE: Diff.additive

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

> I changed the diff. oil in my E34 M5 last week to Amsoil 75/90.I went
> to a drivers school at Sebring this past Sunday and now I'm getting a
> grinding noise from the rear end when I  turn the steering wheel at slow
> speed. Do I need an additive like the GM ltd.slip diff. additive?

	My '89 325i (with LSD) is in a similar boat. 
	I had switched to RedLine 75W90 oil last fall and everything was
going great until I moved from VA down south to TX. Gentle chattering in
small radius turns soon turned into loud roaring. I tried the GM (Corvette)
LSD additive (a pain to add without draining) and it made things marginally
quieter. But not nearly acceptable. I don't know if a driving school and a
few autocrosses have anything to do with it, but the chattering is not going
away even though the temperatures have finally dropped below 80F. 
	I have also noticed that the LSD does not seam to be working as well
as it used to before I started messing with RedLine (RedLine MTL in the
manual gearbox is great, though). Under hard straight line acceleration from
a stop light I can easily persuade the rear end to break loose and start
heading sideways.
	Long story short I will try the heavier weight RedLine 80W140 oil
next (http://www.redlineoil.com/ for more info). If that does not cure the
problem I will go back to dyno juice.

alex
2x M20B25 E30's with LSD's (one chattering with RedLine and the other quiet
with anonymous BMW LSD oil)

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