My "93 F150 (302 V8, overdrive automatic) has developed the a chattering which I think is the lock up torque converter sliping. Only does it when truck is warmed up and at 50 mph or more. Happens in and out of overdrive, but never happens in 2nd gear range no matter what speed. The truck is worth less than $3,000, and trans shop wants a Grand to change torque converter. He agrees with me as to cause of chatter. From what I've been able to find out, there is a wire coming out of the trans that is grounded by the PCM to cause lock-up. Can anyone give me the color code of this wire? I would cut it and go without lockup rather than fork over $1,000. Also would doing this cause a "check engine" light and trouble code? any info appreciated.

 

Well if u do cut it then the check engine light will come on and throw up a code. My throws up a code about the torque converter slipping but I am still driving it.. Mine is locking up when i go from slowing down to mashing in the pedal to make it speed it quicker.. It has been doing this for about 3mouths.. It doesnt do it to bad.. Mine doesn't do it at the speed u are talking about that.. Mine only does it going from 20 to 30 after slowing down tho..