4020 power shift woes

[Madbohemy]

I've got a 1964 4020 power shift. Last fall I was pulling a 400 bushel load of corn up a n incline in 8th gear. When the tractor pulled down to about 3/4ths the rpm the transmission acted like it shifted to sixth gear. I manually shifted to 6th gear and pulled the rest of the way up the hill. I used the tractor to round bale about 200 corn stalk bales and found the transmission to be slow and sluggish, plus the pressure guage on the dash would drop with the rpm. This is not normal with past performance. The pto works fine, but a wanna be mechanic installed a new pto clutch about 500 hours ago. Should I pull the clutch pack out and take it to a dealer for inspection? The tractor is already split. I checked the torsion plate at the fly wheel and it's okay. I haven't had the tranmission pressures checked, I probably should have but money is tight. Any ideas? Thanks.

 

[Ron Anderson]

you can buy the clutch packs at a tractor salvage dealer used. A good place will check them before stripping the tractor to see if they are good. It would have been best to put gauges on yours before you split it so you knew what the problem was. now you will be. guessing.

 

[DLM]

If you have it split between engine and bell housing i would take C1 and C2 clutch pack out & check it out you can also check the trans. pump at the same time,there are 4 sealing rings in the manifold that could be worn,check your clutch plates for ware & worpage.The PTO clutch won"t
have anything to do with the trans. part not working right you have to split it between the bell housing & trans. to get to the PTO clutch.
Make sure the suction screen in the bottom of thr trans. is clean & your filters. Don

 

[rexhellwig]

My own observations:

-Number of years working on Deere powershifts - 28

-Number of junkyard, "rebuilt", or "reman" C1C2 and planetary packs I have seen installed - too many to count

-Number still in service after 500 hours - 0

 

[db990]

This is just a suggestion. We have a JD 4520 power shift that had gear issues. It turned out to be that the gasket to the valve body had some small tears in it that was allowing fluid to blead through and not allowing the right amount to keep the transmission tight. It was a simple cheap fix. P.S. it was the origional gasket over thirty years old.