GMC 2007 Sierra - Manual (Page 426)

Dolly Towing
Front Towing (Front Wheels Off the Ground)
Two-Wheel-Drive Vehicles
Notice: If you tow a two-wheel-drive vehicle
with the rear wheels on the ground, the
transmission could be damaged. The repairs
would not be covered by your warranty.
Never tow your vehicle with the rear wheels
on the ground.
Two-wheel-drive vehicles should not be towed
with the rear wheels on the ground.
Two-wheel-drive transmissions have no provisions
for internal lubrication while being towed.
To dolly tow a two-wheel-drive vehicle, you must
tow the vehicle with the rear wheels on the
dolly. See “Rear Towing (Rear Wheels Off the
Ground)” later in this section for more information.
Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Drive the vehicle up onto the tow dolly.
2. Shift an automatic transmission to PARK (P),
or a manual transmission to FIRST (1).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to the
tow dolly.
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