Automatic Transmission; Shifting Out Of Park (P); Torque Lock - GMC 2004 Yukon XL Owner's Manual

If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is firmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without first pulling it
toward you. If you can, it means that the shift lever
wasn't fully locked into PARK (P).

Torque Lock

If you are parking on a hill and you don't shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may find it 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 2-37.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission,
so you can pull the shift lever out of PARK (P).

Shifting Out of Park (P)

Automatic Transmission

Your vehicle has an automatic transmission shift lock
control system which locks the shift lever in PARK (P)
when the ignition is in the LOCK position. You have
to fully apply your regular brakes before you can shift
from PARK (P) when the ignition is in RUN. See
Automatic Transmission Operation on page 2-24.
If you cannot shift out of PARK (P), ease pressure on the
shift lever and push the shift lever all the way up into
PARK (P) as you maintain brake application. Then, move
the shift lever into the gear you want.
If you ever hold the brake pedal down but still can't shift
out of PARK (P), try this:
1. Turn the key to ACCESSORY. There is no shift
interlock in this key position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the gear
you want.
5. Have the system fixed as soon as you can.
2-39