GMC Yukon XL 2013 Owner's Manual page 433

Here are some important things to
consider before recreational vehicle
towing:
What is the towing capacity of
the towing vehicle? Be sure to
read the tow vehicle
manufacturer's
recommendations.
What is the distance that will be
travelled? Some vehicles have
restrictions on how far and how
long they can tow.
Is the proper towing equipment
going to be used? See your
dealer or trailering professional
for additional advice and
equipment recommendations.
Is the vehicle ready to be
towed? Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.
Dinghy Towing
Two-Wheel-Drive Vehicles and
Four-Wheel Drive Vehicles with a
Single Speed Automatic
Transfer Case
Notice: If the vehicle is towed
with all four wheels on the
ground, the drivetrain
components could be damaged.
The repairs would not be covered
by the vehicle warranty. Do not
tow the vehicle with all four
wheels on the ground.
Vehicle Care
Two-wheel-drive vehicles and
four-wheel drive vehicles with a
single speed automatic transfer
case should not be towed with all
four wheels on the ground.
Two-wheel-drive transmissions have
no provisions for internal lubrication
while being towed. Four-wheel drive
vehicles with a single speed
automatic transfer case have no
neutral position and will spin the
transmission when the rear
wheels turn.
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