401KVet
Well-known member
After driving my 1980 for a couple of months after purchasing it, I thought it may be due to change the oil in the rear end. Not being sure when was the last time. I decided to go with Royal Purple, full synthetic, and the GM Additive. After a few weeks I noticed that I had a oil seepage at the rear end. Someone told me it may have started because of the synthetic. After a few weeks I changed the oil again going with OEM type Valvoline HP gear lube along with the GM additive. The speepage stopped and hasn't returned.
