The clutch is slipping in one range.

1. Rebuild the specific clutch that is slipping.
2. Replace the piston seals.

Oil is leaking excessively at the piston seals in one range.

Overhaul the clutch and piston assembly.

Oil is leaking in the valve components of one range.

Replace or rebuild the control valve body assembly.

The trimmer valve is stuck open.

1. Replace or rebuild the control valve body assembly.
2. Check the trimmer valve for freedom of movement.

The priority valve is cycling.

Replace or rebuild the control valve body assembly.