Ask Away! With Jeff Smith: Turbo 400 Kickdown Switch

Did you know that GM's Turbo 400 three-speed automatic transmission uses an electric switch instead of a cable or mechanical linkage to downshift a gear at wide open throttle? Our friend D.L. didn't know either, so he asked On All Cylinders' resident tech expert Jeff Smith how the TH-400's electric kickdown works.

Of course, Jeff was more than happy to explain how the kickdown switch works, and offered several switch options that are available to if you can't locate or don't want to use the bulky factory switch. It's good reading--and good knowledge to have.

If you somehow haven't seen Jeff's previous Ask Away! columns, not to worry--here's a link to all of the hot rod wisdom Mr. Smith has dispensed so far.