GMC Yukon XL 2013 Owner's Manual page 271

To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower
air dam.
Notice: Operating the vehicle for
extended periods without the
front fascia lower air dam
installed can cause improper air
flow to the engine. Re attach the
front fascia air dam after off-road
driving.
Loading the Vehicle for
Off-Road Driving
WARNING
Unsecured cargo on the load
floor can be tossed about
when driving over rough
terrain. You or your
passengers can be struck by
flying objects. Secure the
cargo properly.
Keep cargo in the cargo area
as far forward and as low as
possible. The heaviest things
should be on the floor,
forward of the rear axle.
Heavy loads on the roof raise
the vehicle's center of gravity,
making it more likely to roll
over. You can be seriously or
fatally injured if the vehicle
rolls over. Put heavy loads
inside the cargo area, not on
the roof.
Driving and Operating
For more information about loading
the vehicle, see Vehicle Load Limits
and Tires.
Environmental Concerns
Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.
Do not park over things that
burn. See Parking over Things
That Burn on page 9 28.
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