Ag Tech - 3/21/2012 22:28
If you can shift into 7th and 8th by using the clutch pedal to make the shift its most likely a stuck or sticking Dump Valve or one of the C clutch valves sticking.
Right Hand side valve needs to come off and its the rectangular valve bolted to the back side. Pay close attention to how free the valves move and check them to the repair manual if they and the springs are in it the correct direction.
well i did try while moving pushing in on the clutch then shifting into 7th and 8th as well letting out on the clutch and it did the same thing we replaced it with a remanufactured unit. Do they test them before they send them out or is it possible that the unit was bad? | 
JD 4640 Clutch pack replaced
