Hey guys - Got a W50 for an 18rg build im working on, and I want to get it installed to make sure everything is good to go internally.

Whats the best way to make sure the internals are clean and ready to go for install, asside from taking the thing apart? I've heard some say kerosene, but I'd be worried about it not drying out all the way and mixing with transmission fluid.

Any ideas? Can you do a flush with a trans thats not installed?

Thanks!

I managed two large transmission shops for about 10 years. We installed used transmissions for people that could not afford rebuilds. This was our standard practice:

Unless it has been sitting out under a tree or something, the inside should be fine. I would replace the input and output seals as a precaution. Before putting any money into it, check rotation by turning the input shaft. Shift it into gears and make sure the output shaft spins. listen for any crazy noises and check for binding. The input shaft should be easy to turn even in gear. Drain the oil it has in it (hopefully its not mud.) Top it off with fresh oil (after it is installed in the car with driveshaft in place) and drive it. Check the level after a few miles. If the new fluid looks old already when you check it, you might consider replacing again. If the old oil was really tarnished, any residue will mix with the new oil and discolor it.

Good luck!

Excellent! thank you for the quick reply. As soon as I get it cleaned up this should service as a perfect pre-install guide.

ok, so all gears turn freely, but 4th and 5th appear to bind up a bit. i can always crank through the bid with just hand power, but its not super fluid like the other gears. I also get a little bit of scratching when i turn the spline in some gears if i put my ear to the casing. could this be sediment?

sounds like i might need to do a flush?