GMC 2003 Sierra - Manual (Page 336)

Dolly Towing
Two-Wheel-Drive Vehicles
TirtiO'wheel "drVe vehicles should not be towed with the
rear wheels on the ground. Two-wheel-drive
Udiismisslons have no provisions for Inlernai lubrication
while being towed. To propsriy tow these vehicleSf
they should be placed on a platform trailer with all four
wheels off the ground.
Four-Whe&l'Drive Vehicles
Use the following prooedure lo tow your vehicle;
1 Firmly set the parking brake.
2. Shift an automatic transmissicm lo PARK (P}, or a
manual transmissinn to FIRST (1},
3. Securely attach the vehicle being towed lo the low
vehicle.
4. Shift the transfer case to NEUTRAL See
Four-W heel Dme- on psge 2-35 for iho proper
procedure to seleci the neutral pcsilion for
your vehicle.
5 k Release the parking brake only after the vehicle
being towed is lirmiy attached to the towmg
vehicle.
6- Turn the Ignition off.
A CAUTION:
Shifting a four-wheel-drive vehicle's transfer
case Into NEUTRAL can cause your vehicle to
roll even [f the transmission ia In Park (P) for
an aulornatic transmission^ or if your vehicle ia
in gear, for a manual transmiasion. You or
others could be injured. Make sure the parking
brake is firmly set before you shift the transfer
case to NEUTRAL.
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