GMC 2010 Sierra - Manual (Page 427)

Dolly Towing
Front Towing (Front Wheels Off the
Ground)
Two-Wheel-Drive Vehicles
Notice: If a two-wheel-drive vehicle is towed with
the rear wheels on the ground, the transmission
could be damaged. The repairs would not be
covered by the vehicle warranty. Never tow the
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, the vehicle must
be towed with the rear wheels on the dolly. See “Rear
Towing (Rear Wheels Off the Ground)” later in this
section for more information.
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