GMC 2007 Sierra 1500 Pickup Owner's Manual page 427

CAUTION:
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Shifting a four-wheel-drive vehicle's
transfer case into NEUTRAL can cause
your vehicle to roll even if the transmission
is in PARK (P) for an automatic
transmission, or if your vehicle is in gear,
for a manual transmission. You or others
could be injured. Make sure the parking
brake is firmly set before you shift the
transfer case to NEUTRAL.
6. Shift the transfer case to NEUTRAL.
See Four-Wheel Drive on page 153 for the
proper procedure to select the neutral position
for your vehicle.
7. Release the parking brake only after the
vehicle being towed is firmly attached to
the towing vehicle.
8. Turn the ignition off and lock the steering
column.
Rear Towing
(Rear Wheels Off the Ground)
Two-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle
from the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. See Parking
Brake on page 169
3. Put an automatic transmission in PARK (P) or
a manual transmission in FIRST (1).
4. Follow the dolly manufacturer's instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the
tow vehicle. Make sure the wheels are straight
before towing.
For manual transmission vehicles, make sure
the wheels are straight before proceeding
to the next steps. On automatic transmission
vehicles, use an adequate clamping device
to ensure that the front wheels are locked into
the straight position.
5. Release the parking brake only after the
vehicle being towed is firmly attached to
the tow vehicle.
6. Turn the ignition to LOCK.
427