OK. I see your point, now.

But I don't see how thicker oil would give you better seal. Combustion pressure is on top of the piston... Rings do the sealing...

I'm very confused.

Function before fashion. '96 Contour SE "Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998