Packard Forum Index » Post-War (1946-54)

What's the best lubricant for the differential/rear end on my 1954 Clipper manual with overdrive? I am using GL-1 90W mineral oil in my transmission and overdrive. Thanks again!

You MUST use an "extreme pressure" or EP gear oil. Many of us use a GL-5 SAE 85-140 though there is nothing wrong with using a single weight EP oil of the viscosity recommended in the owner's manual for your car (SAE 90). I've been using Valvoline's GL-5 SAE85-140 for many years in differentials, standard transmissions and steering gears of Packards from the early 30s thru 1956 without problems. You may have to purchase it in a 5-gallon pail so you'll have enough for a few changes and some for your friends as well.

Thanks again, Owen.