Tractor Repair: Case 1070 with metal in powershift filter, clutch packs, transmission bearings

Question
Hi. I have an originally yellow Case 1070. I have lately been having powershift issues. First it would snub the engine in powershift 1 or reverse. I freed up the spools. It would work for a while and act up again after sitting for a bit. Then one day in the field I lost powershift 2 and 3. Tractor comes to a stop when you shift it into powershift 2 or 3. Pulled the powershift filter and the oil is glittery. no chunks. What are the possible failures in these powershifts that could cause this? The hydraulics work fine.

Answer
It is impossible to know for sure what caused the loss of powershift 2 and 3 without hooking up pressure gauges to all the clutch packs and checking the pressures in all powershift speeds.  The problem is going to be related to C3 clutch, but you will need to find out if there is pressure to it or not.  If there is no pressure to C3, the pilot spool could be stuck.  If there is pressure but the tractor stops, C3 clutch is bad.  The powershift clutches that are engaged in each powershift speed are as follows:  
Powershift 1, C1 and C2
Powershift 2, C1 and C3
Powershift 3, C2 and C3
    Reverse, C2 and C4
When the clutch pedal is down, there should only be pressure on C4.  Clutch pressures should be 195 to 210 psi.
 
 Glittery oil could come from just about anywhere.  Worn transmission bearings, worn powershift clutch plates, worn C1 carrier, worn planetary carrier, worn oil distributor, worn hydraulic pump, hydraulic filters not installed correctly or plugged, etc.  The debris in the oil is what causes the pilot spools to stick, snubbing the engine.