Engine break in oil?

Krooser said

That sludge was a by product of leaded gasoline and fuel dilution. Very outfits ude osrafin based oils anymore but anything out of the old Bradford, PA refinery still is plus Cenpeco and maybe a couple others. Parafin based oils are a cleaner base stock than any other dino oil.

End of my BITOG/540rat-ish reply.

Click to expand...

LOL.. .I like the 540-Rat reference. An interesting fellow....

BTW, the MIL specs for oil in the 80's still prohibited paraffin based oils... so being a 'cleaner base' (whatever that means) is not telling the whole story. It might be the way they reacted to the heat and fuel of the day, etc, and maybe a variable was the whole package (liek low detergent levels). The Quaker State and Pennzoil stuff did sludge up more than other oils for sure. QS and PZ moved away from the paraffin based oils sometime in the late 70's-80's.

I just related the old common experience with them and pointed that out about the Lucas oils... makes me a bit more 'thoughtful' about using it.