Diff and Tranny fluid: REDLINE ok?

Changing all my fluids for the summer season, and since I have two quarts each of redline MTL (for tranny) and 75w-90 (for diff) I figure I could use these in the coupe. Anybody else have Redline in their coupes, or switched over from using dino juice experience any ill or good results?

A lot of the newer guys like redline in the manual trans, and the diff. It is more noisy, however. I personally like Royal Purple.

To quote Carl Nelson in his 5 speed conversion writeup:

"We use a blend of Redline MTL and 80/90 mineral oil 50:50 part for easy shifting and part for noise reduction"

RE: diff and tranny fluid

I also read Carl's recommendation for mixture.
Where would you get 80/90w mineral oil?

In literature it compares redline mtl to 10w/30.
Is mineral oil stable and viscous enough to withstand the Temperatures?
I have NO knowledge.

But have just installed a 5sp, and 3.07 lsd diff.

And inquiring minds want to know.

I filled the empty cases with generic 85/90w, with the intentions of runnig for short period, then draining and filling with ?????

So far the new items are quieter than originals.
And what an increase in driveability.

Tranny & Diff lubes--SwepCo lubricants

Steve--Carls advise is sound--have been running mixture of redline and swepco in BLUMAX 5 speed OD transmission for several years--smooth and very quiet except slight whine in first gear until lube warms--then disappears--my regular diff lube is SwepCo, a high performance lube from a Company used by HD trucking and equipment service ops and several racing teams--my mechanic discovered same and has been using it for ALL BMW customers his shop services--nary a problem or complaint in the 20+ years of using it!! Include me in that group as all my cars are using same!!

Original LSD in BLUMAX lasted 310,000 miles and took a crap immediately following Carls shop--not my guy--installing my 5 spd OD almost 100K miles ago--think his guy either overlooked or missed something as no prior problem had existed on the way there--but--it howled like a banshee on the 90+ mile trip back to Costa Mesa 11 years ago--wasn't sure I would make it home--diff had to be replaced next day--maybe Carls guy had forgotten to install fresh lube--hhhmmm??.

Simply Google--swepco lubricants--for the whole story--very impressive customer commentaries from many heavy equipment operators--they are a hardy and demanding bunch!!

In your climate with its wide temp ranges--and if asked--I would suggest the same for your Coupe. Not sure what Carls favorite mineral based lube is but wouldn't be surprised.

Looked at the Swepco site. Looks like there are several options for gear box fluid. Which formulation do you recommend?

Swepco lubes

I rely on my BMW mechanics long term experience with their products--give Randy Nelson a call--I'm sure he will give you his recipe for the type used in his shop.

Contact me for his phone number:

[email protected]