Deere 850J with "slow to react" right hand drive

[02Dmax]

Customer of mine recently purchased a Deere 850J dozer. If you hop in it and take right off the right side won't pull until the machine warms up. However, if you start it and let it sit for 30 minutes and let it warm up without moving it, it takes right off and has power to both sides. Upon changing directions I've noticed that the right side is just a bit slower to gain power, but I'm talking half a second maybe, it's just enough that if you decelerate, change the travel back to forward, and then go wide open throttle it will pull to the right just a hair before tracking straight again.

I haven't dove real deep into it yet but I have checked wires and plugs on the hydrostat pumps to make sure that at least the harness isn't damaged. Anyone have any ideas? thought about swapping speed sensors side-for-side to see if the issue changes to the other side but wanted to ask for some input first. Thanks!

 

[GaryHoff]

Do the transmission calibration first. If there is a fault, the calibration will fail.

 

[02Dmax]

Do the transmission calibration first. If there is a fault, the calibration will fail.

Ok, how do I go about doing that? Does it require the Deere diagnostic program? Thanks For your help!

 

[GaryHoff]

Quote from service manual, for later serial number units.

"To enter Service Mode, turn the key switch to the ON
position, then push and hold the MENU button down
for approximately 5 seconds until a beep is heard and
Service Mode temporarily appears on the Main Menu."

Follow the service screens to calibrate TCU. Before you try and do a calibration, have the unit at operating temperature (its best if its been working a few hours. Also, I usually have the unit up in the air, as its easier to calibrate. The unit goes really fast in its high speed calibration, and you cant steer or it will fail the calibration.

 

[02Dmax]

Thanks!