Manual Downshifts
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Manual downshift testing is not required for vehicles equipped with Driver Shift Control (DSC). This is done by shifting the gear selector to M on the display and then by using the + and - on the rocker switch on the gear selector. The TCM and shift solenoids 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 4th gear.
- Release the throttle and apply the brakes
- Verify the downshifts occur as commanded.
Accelerating Upshifts
- Place the gear selector in the M position.
- Press the - until the display shows M1.
- Accelerate slowly and keep the throttle steady not going over 3,000 RPM Engine speed.
- Press the + on the gear selector.
- Verify the upshift occurs as commanded. Repeat step 4 to verify the remaining gears.