ah the good ole cheap partsmaster
I would be all too interested about this oil
and also where your dad gets it from
we have a chain down here called Bennet Auto Supply that carries partsmaster stuff
we get their filters at our shop at like 1-2 dollars a piece, they use the same numbering system as Wix, but with a 6 on the front instead of 5.......
they make belts, suspension parts, most of it seems pretty [censored] cheap, and the price of it is.... the belts didn't look half bad though