GMC 2009 Sierra - Manual (Page 110)

Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle can put too much force on the parking pawl in the
transmission. It might be difficult to pull the shift lever out
of PARK (P). This is called torque lock. To prevent torque
lock, set the parking brake and then shift into PARK (P)
properly before you leave the driver’s seat. To find out
how, see Shifting Into PARK (P) on page 2-33.
When you are ready to drive, move the shift lever out of
PARK (P) before releasing the parking brake.
If torque lock does occur, you might need to have
another vehicle push yours a little uphill to take some of
the pressure from the parking pawl in the transmission.
Then you should be able to pull the shift lever out
of PARK (P).
Shifting Out of PARK (P)
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
• Prevent ignition key removal unless the shift
lever is in PARK (P) with the shift lever button fully
released, and
• Prevent movement of the shift lever out of PARK (P),
unless the ignition is in ON/RUN or ACC/
ACCESSORY and the regular brake pedal is applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than 9
volt) battery.
If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. See Jump Starting on page 5-40 for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Then press the shift lever button.
3. Move the shift lever to the desired position.
If you still are unable to shift out of PARK (P):
1. Fully release the shift lever button.
2. While holding down the brake pedal, press the shift
lever button again.
3. Move the shift lever to the desired position.
If you still cannot move the shift lever from PARK (P),
consult your dealer/retailer or a professional towing
service.
2-34