Chevrolet 2003 Impala Owner's Manual page 99

Torque Lock
If you are parking on a hill and you don't shift your
transaxle into PARK (P) properly, the weight of
the vehicle may put too much force on the parking pawl
in the transaxle. 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 lnto Park (P)
on
page
2-27.
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 transaxle, so you
can pull the shift lever out of PARK (P).
Shifting Out of Park (P)
Your vehicle has an automatic transaxle shift lock
control system. You must fully apply your regular brakes
before you can shift from PARK (P) when the ignition
is in ON. See Automatic Transaxle Operation on
page 2-23.
If you cannot shift out of PARK (P), ease pressure on
the shift lever by pushing it all the way into PARK (P)
while keeping the brake pedal pushed down. Release
the shift lever button if you have a console shift.
Then move the shift lever out of PARK (P), being sure
to
press the shift lever button if you have a console shift.
If you ever hold the brake pedal down but still can't
shift out of PARK (P), try this:
1. Turn the ignition key to ACC.
2. Apply and hold the brake pedal down until the end
of Step 4.
3. Shift to NEUTRAL (N).
4. Start the engine and shift to the drive gear
you want.
5. Have the vehicle fixed as soon as you can.
2-30