Torque Converter

[wvsvx]

At about 70 to 80, after a few miles of driving, the car jerks noticeable but there are no engine indications. I am guessing that the TC or something in the trans is malfunctioning. Where should I start?

[lee]

does it do it once or twice then stop, or does it continue to do this?

I've noticed in certain temperature ranges my car will seem to go for TC lockup, then immediately fall out of lock-up (assumed from watching the tach at steady speeds). Usually only does it once. Not sure of the lock-up mechanisms temperature sensing rountine, but I always attributed it to this.