Need help on NP205 Lubrication - The 1947 - Present Chevrolet & GMC Truck Message Board Network

DrMaserati · 08-03-2003, 03:32 PM

The current trend is to using heavy motor oil in t-cases and manual transmissions. Generally 30w to 50w. Seems to work as well as 90w gear oil and makes for easier shifting. And I believe some chain drive cases specify auto trans fluid. I think there is a common misconception that auto trans fluid doesn't lubricate well, but keep in mind it is the sole lubricant in an automatic transmission and works very well for that purpose.

The exception would be a differential, where it is still necessary to have an oil with EP additives.

JP

08-03-2003, 03:32 PM	#1
DrMaserati Village Curmudgeon Join Date: May 2003 Location: Salem, OR Posts: 75	The current trend is to using heavy motor oil in t-cases and manual transmissions. Generally 30w to 50w. Seems to work as well as 90w gear oil and makes for easier shifting. And I believe some chain drive cases specify auto trans fluid. I think there is a common misconception that auto trans fluid doesn't lubricate well, but keep in mind it is the sole lubricant in an automatic transmission and works very well for that purpose. The exception would be a differential, where it is still necessary to have an oil with EP additives. JP __________________ 78 Chevy K30 duallie, 454, TH400 78 IH Scout II, 4X4, 345, 727TF 76 IH Scout II, 4X4, 345, 727TF 65 IH 1200C pickup, 4X4, 345, 4 spd 48 IH KB-8-F, RD-450, 5 spd, 35,000 GVW (a REAL truck) "Life is too short to drink cheap beer." Harry S. Truman



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