1971 Chevy C10 Transmission Fluid V/S Differential Fluid?

[P51P28]

Is it me or do I need more coffee? For the life of me, I can't get a clear answer if the fluid for my limited slip differential is the same fluid i need for my 3-speed manual transmission. Will an 80w90 GL-5 fluid from the same bottle work for both? Just going by the 1971 Chevy users manual. I'm currently under the impression that transmission fluid isn't the same as differential fluid. Thanks for the clarification. And now....more coffee. Great to be here on this site.

 

[MolaKule]

Look at G for your manual transmission. Today's GL-4 application-specific offerings are much better than lubes of yore.

Thread 'Updated List of MTFs May 1st, 2026'

May 30, 2024

Updated List of Manual Transmission Fluids Updated May 30th, 2025

NOTE: This list is only a “summary” list of MTFs available in the MTF Lubricant Market and only available in US auto parts stores and US Import outlets. It is not an endorsement nor a critique of any one fluid, nor is it implied that any one fluid will cure problems in MTs that have design problems or those that have excessive wear. Viscosities listed are at 100C and rounded up.

A.These MTL fluids are closest to a Kinematic Viscosity of 6.X cSt@100C (About the same viscosity as Dexron VI ATF) LV MTF's:

1. HPL Manual...

• MolaKule
• Replies: 0
• Forum: ATF, Differential, Trans, Brakes, P/S

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Your hypoid differential will require a 75W90 with a GL-5 rating.