Recently purchased an old D3b, worked fine for about an hour after I got it home, then transmission stared to fail it seems. I changed the fluid with a premium brand from the local farm store that met Cat specs. There appeared to be water in the old fluid, a bit milky looking. It worked fine for about ten minutes, then it stopped. It acts like it is trying, but just cant seem to catch. Any ideas? I have ordered a shop manual, but it will be a couple of days before its in. I dont pretend to be a heavy equipment mechanic, but I have worked on old equipment all my life, its my hobby I guess. Any help pointing me in the right direction is greatly appreciated.
Check the screen in 3F/1R trans or the filter if 3F/3R transmissions. If lots of black flakes clutch packs could be worn out.
That sounds like a unlucky break , Dave was right about the filter and the screen in the bottom of the transmission pan. I would clean the screen , and replace the filter up top. a little trash can stop up the small ports and lines , also it may take a little more engine rpm to get it going . good luck .