Originally Posted by
DJ_Martin
the "new" transmission in the truck is a used one that was rebuilt about 20k ago, and the FTI converter wasnt a billet one, just the $400 summit sales. O-ring looked good on input shaft. It is in a 2003 Silverado, no swap. I fear it could be a mechanical problem, but i wanted a second opinion on my tune, being that the last used transmission i put in did the same thing. I've checked misfire monitors, they are all up, also when i tap my brakes it doesnt lock the converter up like it should, could a bad neutral safety switch cause this?