1066 torque issues

[KY Reed]

I am helping my cousin work on his torque in his 1066. He changed the filter (oem filter) before he pulled last weekend and when he pulled, the torque slipped at the end of the track. When the tractor is running, whether the torque is in high or low, the pressure is 280 to 290 psi. When you shift from high to low or low to high, the pressure drops to 210. It will stay that way until it is throttled down and pressure will rise when the throttle is opened back up. He has to throttle down
and back up every time before the pressure will return after a shift. What should he be looking for?

 

[used red MN]

The attached may be helpful. If you ever watched Hee Haw the doc on there has your answer. It slips when I do this ..Then do not do that..! ha ha
Hydraulic TA troubleshooting guide