What does it take to make 20k mile oil?
One of my fravorite You Tuber's, Jason Fenske, at Engineering Explained gives us an inside look at what kind of R&D it takes to make a 20k mile oil. Notice the 500k test miles they put on the Silverad...
Forum Discussion
To the guy that posted "AMZ/OIL" you are right on. My Dad was the first Dealer in WA back in the early 70's. PENZ/OIL did not like the similarity so they had to go to AMS/OIL.
