Diff. Oil, what type?

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Jun 10, 2003 | 11:24 AM

Jeffski

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From: Burlington Ontario

Diff. Oil, what type?

I know it has been covered in some previous threads, but what type of oil do you use combined with what firction additive for my rear diff. The car is a 77 with 3:08 gears / Automatic.

Thanks
Jeff :yesnod: :yesnod:

Jun 10, 2003 | 12:17 PM

Gator81

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From: far, far away

Re: Diff. Oil, what type? (Jeffski)

Hi, Jeff.
I'm using Mobil 1 synthetic gear lube, 75w-90, GL-5, with one 4-oz bottle of the GM posi-traction additive. Can't recall exactly how much lube it takes to fill the diff. Seems like it was two of the 1-liter bottles. :seeya

Jun 10, 2003 | 12:38 PM

1LE

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From: Haysville Ks

Re: Diff. Oil, what type? (Jeffski)

I recently changed mine, and stayed with all GM lube and addative.

Jun 10, 2003 | 01:47 PM

LT-1 Larry

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From: Bellevue WA

Re: Diff. Oil, what type? (Jeffski)

Getting ready to put mine back in this week. The rear-end guru who rebuilt it says to go with synthetic (like the GL-5) and GM addative.

Jun 10, 2003 | 02:20 PM

Gator81

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Re: Diff. Oil, what type? (1LE)

If I were doing it again any time soon, I'd be tempted to go with the GM standard instead of the synthetic. With about 105K miles on it, there was a slight seep at the seals with the old lube, but now there is noticably more leakage past the side yokes with the synthetic. Not a big deal yet, but still not a good thing. I like the features of the synthetic, but increased seepage seems to be in issue.

Jun 10, 2003 | 04:06 PM

PatG

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From: Katy TX

Re: Diff. Oil, what type? (Jeffski)

I just use the GM stuff, seems to work fine for me.

Jun 10, 2003 | 05:23 PM

mvftw

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From: Long Island NY

Re: Diff. Oil, what type? (PatG)

I just changed mine... GM additive & Castrol 80w-90 dino

Jun 10, 2003 | 06:37 PM

mapman

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From: Wichita KS

Re: Diff. Oil, what type? (Jeffski)

I just used the GM Limited Slip Axle Additive #1052358 (4 oz), and the GM Axle Lubricant SAE 80W-90 #1052271 (0.68 L) as specified in the shop manual.