Hi gta007,
If it is the TCM, it would normally cause the D4 light to blink when the problem occurs.
Possible causes for the slipping in reverse are :
Defective 4th Clutch Or 4th Accumulator
Feed Pipe "O" Ring Damaged
Servo Valve Stuck
Since the problem is intermittent and you do not have flaring when shifting into 4th gear, I would suspect the servo valve to be the most likely cause.
When it is stuck, the problem occurs and after repeatedly shifting in and out of reverse, the servo valve starts working and the problem goes away.
If the fluid had not been replaced for a long time, replacing it might reduce or eliminate the problem.
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Wednesday, June 24th, 2009 AT 8:33 AM