FOUND out how to fill the transmission
October 10th, 2015.
Profo:
What model of Unimog do you have? On the S404.114 the transmission filler is to the left rear of the passenger seat just in front of the cab rear wall, and it also houses the dipstick for the tranny. Maybe yours is similar?
Think I figured it out it wasn't one of the Germans best ideas, there are actually, four drain plugs on the FLU-419 for transmission, one on the rear, and three under, I tried all i could to get fluid to the front section which is a no go, so I dropped the bottom transmission cover and figured it out, internally there is a over flow between the transmission and the PTO area sort of like a dike or weir , it is the same exact height as the filler plug hole on the side so what happens is once you fill the rear section the front DOES NOT get any oil until you start it which once you start the SEE (FLU-419) it flings oil into the front section which is very slow so you are in essence running your bearings dry until the front section fills up then it overflows back into the rear section, the problem with this is now your rear section is now NOT at the proper fluid height as indication by the filler side plug. the proper way I found to fill is, you fill the rear with the only side plug there is, till its full, then i made a rubber plug to stick into the front drain drain hole and pump fluid into it until the rear starts over flowing again at the side plug, this means both sections are full. I also tried picking up the rear of the truck till the rear tire were 2 feet off the ground and fluid will go to the front also.You can fill the rear when its level once you start it but by judging the oil going to the front which I watched after starting it would take about 5 minutes of running for it to fill and I didn't want to chance burning bearings.
