Originally Posted By: CATERHAM
PU is a quality oil but I'm not impressed that it's VI is no better than a dino and actually inferior to PP.
But everything is relative. At $5/qt it's not cheap enough interest me but if it drops to $3 bucks, why not, especially for summer use.
That's only because you haven't tried it. I ran PU 5w-30 last summer in my supercharged Mustang GT 5.0 (540HP) and it was exceptional. Shear was non-existent, consumption was low and wear metals and nitration were excellent.
What's interesting about PU 5w-30 is that the V100, V40, HTHSV and NOACK are all within a few percent of those values for Redline 5w-20. I had the Redline on hand so I ran it for the winter, but I'm not expecting better results than I had with the PU.