Hybidder,
For giggles I would block beneath one side of the mast after tilting back, then tilt forward to lift one drive wheel off the ground. Start machine, shift F N R N. If the lifted tire tends to stay spinning in forward this can be an indication of a failed forward pack due to overheated/ warped transmission discs. There should be some plugs on the control valve or on the transmission case, that may have F R and P. If you were to unseat a gauge in the Reverse port and saw 140-155 psi, then would expect to see the same on the Forward port. If tire did not spin on previous test, and the F pressure is very low, and your valve is working correctly, then I would suspect a blown clutch pack piston seal OR a leaking oil distributor seal (end of the shafts).
As mentioned, general procedure is to remove the mast, then pull diff/trans together out of front them disassemble on bench. Good luck!
what I do is hold the engine a cross up with my hoist and with metal cross for security support, and I have all the space I need to change my clutchs with out pulling out tranny, be very sure you hold your engine very good and the metal frames across
If it has a u joint you can pull right out.if not I always pull mast and then tranny/axel as unit so its out and you can then seperate.Sorry I know thats not what you want to hear