Hello,I have a 92 G20 Van 5.7L 700 r4 trans. I'm the original owner,it has 66,000 miles.

I've had this problem since almost new,unfortunately it only had the 12 month 12k mile warranty and started after that.

The Torque converter unlocks and locks with the windshield wipers on.It has always only done it with the wipers on,I seldom ever get caught in the rain with it so never was too concerned about fixing it. Now after towing my boat and having the lights on it did the erratic lock and unlock again. I have tried loading the electrical system before by turning the lights,frt and rear blowers on high and everything electrical except the wipers and it would not do it.

It has a new battery and the alternator is charging 14-14.5 volts w/o load and 13.9 loaded.

I've held up on the brake pedal and have never had them stick on,and after locked up and touching the pedal it unlocks.

Anyone ever heard of anything like this before? Any suggestions where to start troubleshooting? TIA