[ghostrider]

I have a 1982 JD 4440 with power shift.
I have replaced the clutch and transmission pump but the problem is not solved.
after 20-30 minutes of use either with a front end loader or chisel plow on 3 point I will be in reverse to turn or unload hay and the tractor slips out of gear, it wont go forward or backward. All hydraulics still work. It only happens when going in reverse. The dealership has had it 3 times and can't figure it out.
the next step is to go in the back of transmission.
Any thoughts on what is causing this?

 

[albertabuck]

Well not enough info in your post to make any kind of long distance diagnosis, so not even gonna try

The transmission needs to be pressure tested as per the service manuals and the results will tell you what is wrong. I'm amazed your dealer has not done this already as it is the first step in diagnosing issues with any powershift tranny.

 

[farmshop]

I know on older tractors the main pump is fed from the tranny pump and when they get weak they dont supply as much oil in reverse.

 

[SWFarmService]

Sounds like a leak in the reverse pack, hopefully not

 

[ghostrider]

I agree the local dealer seems to be over their head in this one. They did a pressure test on the second visit and said they were weak but within operating range. on the third visit they relaced the clutch and transmission pump. They now have it for the fourth time and plan to explore the rear transmission. I have talked with several mechanics and other farmers and no one has ever experienced this. We pulled a heavy disc for two days after the clutch and transmission were replaced and not a problem. start loading and unloading hay and using reverse more often and it just stops movement. Engine remains running, hydraulics are all working it just wont go forward or backward. you can shift up to 7th and 8th gear and it kills the engine. Linkage is good.
thanks for the relplies!

 

[madcow]

this might sound like a long shot but had it happen on one tractor.


behind the left side battery box in front of the rear axle is the tow disconnect. I had a tractor that would go forward all day, but backing up for planting and sometimes it could back up for ever. other times he could back up 25' and the tractor would quit moving forward or reverse until you shut it off. then the tow would re engage. the pin was missing to hold it engaged.