Road Test: Notes

The transmission control module (TCM) calculates upshift points based primarily on 2 inputs: throttle angle and vehicle speed. When the TCM wants a shift to occur, an electrical signal is sent to the shift solenoids which in turn move the valves to perform the upshift.

The shift speed charts reference throttle angle instead of 'min throttle' or 'wot' to make shift speed measurement more uniform and accurate. Use a scan tool to monitor the throttle angle.