Hummer H2 2009 Owner's Manual page 348

Tow/Haul Mode
Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. See Tow/Haul Mode
on page 2-36 for more information.
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Pressing this button at
the end of the shift lever
turns on and off the
tow/haul mode.
This indicator light on the
instrument panel cluster
comes on when the
tow/haul mode is on.
Tow/Haul is designed to be most effective when the
vehicle and trailer combined weight is at least 75 percent
of the vehicle's Gross Combined Weight Rating (GCWR).
See "Weight of the Trailer" later in the section. Tow/Haul
is most useful under the following driving conditions:
•
When pulling a heavy trailer or a large or heavy load
through rolling terrain.
•
When pulling a heavy trailer or a large or heavy load
in stop and go traffic.
•
When pulling a heavy trailer or a large or heavy load
in busy parking lots where improved low speed
control of the vehicle is desired.
Operating the vehicle in Tow/Haul when lightly loaded or
with no trailer at all will not cause damage. However,
there is no benefit to the selection of Tow/Haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/Haul is
recommended only when pulling a heavy trailer or a large
or heavy load.