I've yet to change the oil in my 31, but it's only been a few miles since the previous owner had it changed.
Back in the 60's when my dad had a salvage yard and used car lot, we used Mobil Delvac, which was for diesels. It was much cheaper than other brands and came in a plain white cardboad can with no lettering or logo. You could only buy it by the case.
I had planned on using the 20w50 Castrol I use in my Brit cars..and in my 94 Pickup. It seems to be just the thing for older, higher tolerance cars.
