GMC Yukon 2007 Owner's Manual page 437

Hitches
It's important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough
roads are a few reasons why you will need the
right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
(A) Body to Ground Distance (B) Front of Vehicle
When using a weight-distributing hitch, the hitch
must be adjusted so the distance (A) remains
the same both before and after coupling the trailer
to the tow vehicle.
If you use a step-bumper hitch, the bumper could
be damaged in sharp turns. Make sure there is
ample room when turning to avoid contact between
the trailer and the bumper.
If you will be pulling a trailer that, when loaded,
will weigh more than 5,000 lbs (2 270 kg) be sure
to use a properly mounted weight-distributing
hitch and sway control of the proper size.
This equipment is very important for proper vehicle
loading and good handling when driving. Always
use a sway control if the trailer will weigh
more than these limits. You can ask a hitch dealer
about sway controls.
437