Has anyone had problems with transmissions and/or transfer cases leaking after switching to synthetic? My transfer case is only a couple of years out of a Marlin 4.70 build so I am sure it is fine, but my transmission is old a tired. I don't want to spend the money for the change and then have to go right back due to excessive leaks. I don't think there is any leaking currently that I can tell. My transmission shifts very rough (almost grinding gears) when down shifting into 2nd and up-shifting into 2nd and 3rd (when cold it is worse). Do you think that switching to redline would help? It got slightly worse when I installed the Marlin 1600 clutch, but I think it is mostly because it engages very near the floor and I am not in the habit of completely depressing the clutch.