Tractor Repair: case 1370 powershift problem, clutch pedal, climbing a hill

Question
case 1370 powershift hub bolt replacement.  I was pulling a heavy implement on a steep field.  I had to frequently shift from 2nd to 1st.  When I would shift to 1st the tractor would delay the shift and then lock in sometimes actually lifting the front off the ground. All of a sudden I had no ps gear but 2nd. No 1st, 3rd or reverse. Now with no load I can start out in 2nd and after going, I can shift to 3rd and to first, but when I do the hoist drops and if any power is needed such as climbing a hill, it jumps and I eventually lose 1st gear. I have replaced the transmission oil and the filters to no avail.  Someone told me there are 6 3/8 bolts that hold the hub.  Is this something that can be replaced without a tractor split? I have reasonable mechanical ability, but do not have the equipment to do a split. Thanks.  BSA

Answer
Hello,

  There are some bolts holding the C2 and C3 clutch carrier together that sometimes break, so I assume those are the bolts you mean.  There are 4 clutches inside the powershift, and 2 of them need to be pressurized at a time to give you the 3 forward powershift speeds and reverse.  The sequence is as follows:

Powershift 1, C1 and C2
Powershift 2, C1 and C3
Powershift 3, C2 and C3
 Reverse,    C2 and C4

  As you can see, 2nd powershift is the only one that does not use C2 clutch, so if you lose 1st, 3rd, and reverse, C2 clutch is the problem.  If the bolts are broken, you probably would not have 2nd either, so I doubt that's the problem.  The only way to know what's going on is to put pressure gauges in the test ports of the powershift control valve and test all the clutches in all the speeds.  There has to be 200-210 psi to all the clutches.  If you don't get pressure to C2 clutch or if it is low, there are a few possibilities to check.  C2 is the one modulated by the clutch pedal, so check the linkage between the pedal and the valve.  There could be a pilot spool stuck in the control valve.  There could be an internal problem such as C2 piston seals leaking.  If the pressure is low in all the speeds, but even lower in 3rd, then the bolts could be broken.  The control valve is under the cab floor and can be worked on through the hole in the floor, but anything else requires splitting the tractor.