John Deere 750B

[Koldsmoke]

I have a 1984 John Deere 750B Dozer which won't move forward or reverse after sitting for a couple months.
When I start it after sitting for a few months the transmission pressure gauge falls into the red zone and it will not move forward or reverse. Blade functions as it should and engine starts and runs great.
However, If I remove and replace the transmission hydraulic filters with new ones, it will start right up, transmission pressure gauge will climb quickly to around 225 psi, and magically it will move forward and reverse as it should. If I use dozer frequently, all is fine, but once it sits again for a couple months, the problem starts all over again. Any advise on this subject would be greatly appreciated.
 

[jm.]

Pretty common oil draining back from the pump. Next time you use it park it with the back end on a log or bank where the front is quite a bit lower, bet it will move.
 

[Koldsmoke]

Thx for the advise. I will try that. Hopefully that works, as the pair of hydraulic filters are not cheap.