It has 220k miles on it. One owner. The old oil could have been original. We went with Redline MT-90 for a few reasons. MT-90 was cheaper than OEM from the dealer. Redline seems to have a good reputation amoung VW geeks. Redline lists our engine/trans in the application finder on their website. And Redline says MT-90 is a GL4 service class, which is what Bentley and I presume VW specify, although API retired GL4 quite a while back.
There is a ton of transmision lubrication info in "Synthetics, Mineral Oils, and Bio-Based Lubricants: Chemistry and Technology", edited by Leslie R. Rudnick. Here's the google book:
https://books.google.com/books?id=9YXRBQAAQBAJ&pg=PA459#v=onepage&q&f=false
We could have gone even cheaper and used synchomesh, but Pennzoil doesn't list our eng/trans, doesn't proclaim GL4, and is known to change how transmission operates (for the better when it is not shifting right). But our 02M was working without any issues, so the goal was to keep it operating the same.
With MT-90 now, shifting feels the same as before.
