papabeach
Member
GL4 for the win! Shifts way better. The Amsoil product is great and so is redline MT90.
GL5 won’t hurt it but it will make it shift worse. Only hypoid gears need GL5. Helical gears in trans and tcase can use it or GL4 happily.
I have been running Redline MT90 for years and been happy. With my recent crawl box woes my rear transmission seal failed and I ran the tranny dry and am sure I roasted some bearings…I have done two short interval fluid changes (with Redline) in hopes of cleaning things up and hoping I might salvage some impending disaster. (I have a bearing noise on cold starts that goes away when you step on the clutch and comes back when you take your foot off. After driving around for a bit it goes away). Maybe I will run this GL5 for a month or so then switch to the Amsoil GL4 and see if anything changes. I actually thought things shifted nicer after replacing with GL5 but perhaps that’s because the other stuff was dirty, though it was still somewhat clear. Time will tell…Hopefully my bearing noise goes away!!! If I need to rebuild my tranny I need to start looking for a shop. I know Marlin has a good reputation but their turn around is terrible…I would have to source a spare transmission to send them just to make this make sense…hoping I can find something local if I need to go this route.