got my tranny with a decent torque converter & put in my 95 longbed plow truck, & sometimes when I'm climbing a slight grade at 50-55 it kicks out of lockup, then back in, then back & forth a few times until I crest the hill then it goes back to normal.
It sporadic, which makes it more aggravating. But when it does it, its always on a slight long climb.
Any ideas?

 

hi
check out your tps ,it may be bad !

 

I would Check the adjustment on the tps cable to tranny it could be to tight