I use mostly Mobil 1, but back in the day my dad bought whatever was on sale for his old 4x4 Bronco.... he ran it hard but changed the
oil/filter at regular intervals,then when he bought a new 4x4, parked it for 5 or 6 years before giving it to me... I restored it and during that time, the clutch froze up on it,it was easier to pull the motor to change the clutch than the trans/transfer case and all the related stuff...about the same time, the valve covers were leaking as well as the
oil pan and seals, I guess from sitting up so long. I brought the motor to a local mechanic cause I didn't have the time to work on it, he changed all the gaskets and dropped the pan and put in a new
oil pump (had near 100,000 hard miles on the 302)... When I picked it up he asked about the brand of oil and I told him whatever was on sale and at one point dad bought and used a case or two of re-refined oil cause it was so cheap. The mechanic laughed his butt off, saying that was the cleanest engine he had ever seen with that many miles on it internally.. Said inside the oil pan looked like it had 500 miles on it as well as under the valve covers!!!!!!!!!!!! go figure!!!!!!!!!!!!and we spend big bucks on
synthetic and name brand oils!!!!!!!!!
David