Shifting problem

[Jackpine]

For those of us who are metrically challenged, his speed was about 36 mph in good old "English" units. That's actually a pretty low speed to be seeing 4th gear (unless you have a fairly high gear ratio?). And, I'd suspect the TC was trying to make up it's mind whether or not to stay locked. If this is a typical cruising speed (around town), I think I'd try changing the TC lock/unlock points. It sounds to me like the TC is trying to lockup when the RPM is too low, then it finds there's not enough power, so it unlocks, and then it thinks things are ok so it locks, ....

Just my opinion, and I'm sure Bill has many better thoughts.

- Jack