Tractor Repair: 3588 2+2 Torque, small screws, snap ring

Question
I have a 1979 IH 3588 with about 3,000 hrs.  The problem is that the torque will not shift out of low range.  When you move the lever no speed changes, the tractor still drives fine but will overrun when goning down hill.  Any ideas?  Thanks.

Answer
Hello,

  There is a chance that the TA has an internal problem, but it might be as simple as the cable between the TA lever and the control valve.  If the cable is not adjusted properly or if the mounting screws come loose, one of the symptoms is the tractor overrunning down hill.  Check where the TA shift cable mounts to the top of the transmission.  There are a couple of very small screws and a clamp that hold the cable in place.  Sometimes these screws come loose and the cable moves, which throws it out of adjustment and then the TA doesn't work correctly.  Also check the upper end of the cable where it mounts to the firewall of the cab.  Make sure the cable is in good condition and the adjusting nuts are tight.  Watch the TA shift spool as someone moves the TA lever in both positions.  The spool should move down to within 1/16 of an inch of the snap ring.  You will probably see by the paint marks on the spool where it normally stops.  When the spool moves up, it should move at least an inch.  If all these things are OK, then the TA will need to be repaired.