Alan777

Rearend's out of my 88 Auto, and I need some differential fluid for my Dana 44. I've heard great things about redline, but i have a few questions.

1. What weight should i run, 75w90 or 75w140?

2. SHould i use the regular synethetic or the "heavyweight shockproof"

3. Do i still add two bottles of GM Limited slip additive to the fluid? Are you guys picking up this LSD additive from the dealer?

96GS#007

Use 75W90
Use the regular
You do not need LSD additive, it's part of the Redline formulation

I've run the above for years, both on the street and on the track (road courses, so LOTS of left and right turning, high speeds, and corresponding heat) without issue.

85vet

I run the heavy shock with no additives - I swear by it.

383vett

When I had a Dana 44 I ran the 75/90 with good results. In my 12 bolt, I use the lightweight shockproof.

93Rubie

I got regular 75W90 Redline in my D44. No complaints works fine, NO LSD additive.

Also, got their Lightweight Shockproof Gear Oil in my ZF6, no complaints, works great, and I know my ZF6 is well protected.

The shockproof, gives more cushion to the gears so it maybe beneficial to run it in high load applications like all of other posters here so far. They all race in some capacity. Me too, just not as often as I would like.

96GS#007

I too run the lightweight shockproof in my ZF6 for exactly the reason cited above.

383vett

That lighweigh shockproof has to be good. It looks like a strawberry milkshake.

flightmate

I'm running MTL in the ZF6. No complaints so far. Have either of you used it, and if so what made you switch to the shockproof?
As for the original question, I also run Redline in the rear with no LSD additive and have nothing but good things to say about it.

96GS#007

I ran MTL for a few months. What I found was that after 12-15 minutes of on-track activity, the shifting quality became very poor. After an extended cool-down, the shifting was once again normal. With the lightweight shockproof, I've run uninterrupted for over 1 hour on the track with no shifting issues.

In addition, given the amount and speed of shifting that occurs on a road course, I like the cushioning effect that the shockproof offers the gears.

93Rubie

Like 96GS#007, I run my ZF6 hard. Not like he does, but hard nonetheless, fast power shifting at redline under WOT on the dragstrip and sometimes the street.

I had it recommenced to me so I am using it. WAY better than stock fluid.

FYI, the fluid is blue so...blueberry milkshake.

96GS#007

We call it Smurf blood