On the drivers side of a TH400 trans there is a male electrical connector, mid way between the shift and the speedo, is that for a back up light? If not what is it? Thanks, and Happy New Year!
early non-Chevy 400s have two pins, one is for the variable pitch torque converter, the other is kickdown. Some 400s from the early 70s have two pins, one is for TCS and the other is for kickdown. If there's just one contact, it's for kickdown. Just needs to get 12v at full throttle. You don't need it, but it makes driving more fun.
Lokar makes one that goes on the trans. I never hooked mine up, I just downshift it manually http://lokar.com/product-descriptions/hitech-th400-elect-kd-kit.htm