Manual Downshifts
Manual downshift testing is not required since all vehicles equipped are also equipped with some form of Driver Shift Control (DSC). The TCM will automatically override DSC downshifts to protect the transmission from damage.
Coasting Downshifts
- Place the gear selector in the DRIVE position.
- Accelerate the vehicle to 6th gear with the TCC applied.
- Release the throttle and apply the brakes
- Verify that the downshifts occur as commanded by monitoring gear ratio, which should change after commanded gear changes.