Tractor Repair: 1070 power shift case tractor, emery cloth, temperature gauge

Question
when the outside temperature is above 95 degrees and I have ran the tractor for an hour or more,when I push in the clutch to stop the tractor and then then let the clutch out the tractor wont move. If you leave the clutch pedal out, for a while,it will finally move. When it does go, it is with a severe jerk. It does this in forward or reverse. It doesnt do it everytime. the transmission temperature gauge says the temperature is OK and the transmission pressure gauge says the pressurs is OK. I have changed the filters and the transmission fluid. I use HyTran- Ultra in the transmission.

Answer
  The pilot spools in the powershift control  valve could be sticking.  They should be removed and cleaned, and if there are scratches or score marks on them, polish them with fine emery cloth.  The control valve is on top of the transmission under the floor plate.