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djgodden's avatar
djgodden
Explorer
Apr 28, 2016

Differential fluid thoughts/recommendations...

I'm getting ready to put a new larger differential cover onto my TV differential (2012 4x4 2500 Ram Laramie Longhorn w/6.7 Cummins). The standard fluid is 75W-90 for rear and ATF+4 for front. Should...
Tow Vehicles
C_Schomer's avatar
C_Schomer
Explorer
Apr 30, 2016
FWIW, Several OEMs went to finned aluminum covers as they went up in power and tow ratings. I use a minimum of syn 75w140 in the rear diff. RP 85w140 has done the best for me in 3 tow vehicles... the best UOAs,longest life and zero wear metal on the magnets. Try whatever you want but the most important thing is to watch for metal on the magnet. You can't even trust UOA if the metal is on the magnet and not in the oil sample... BTDT! Craig

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