GMC Sierra Denali Classic 2007, Owner'S Manual, Page: 305 / 502

If You Do Decide To Pull A Trailer
If you do, here are some important points:
•
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you’ll be driving.
A good source for this information can be state
or provincial police.
•
Consider using a sway control. See “Hitches”
later in this section.
•
Don’t tow a trailer at all during the first
500 miles (800 km) your new vehicle is driven.
Your engine, axle or other parts could be
damaged.
•
Then, during the first 500 miles (800 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of
your vehicle wear in at the heavier loads.
•
You can tow in DRIVE (D). You may want to
shift the transmission to THIRD (3) or, if
necessary, a lower gear selection if the
transmission shifts too often (e.g., under heavy
loads and/or hilly conditions).
Three important considerations have to do
with weight:
•
the weight of the trailer
•
the weight of the trailer tongue
•
and the weight on your vehicle’s tires
Tow/Haul Mode
Tow/Haul is a feature that assists when pulling a
heavy trailer or a large or heavy load. The purpose
of the Tow/Haul mode is to:
•
Reduce the frequency and improve the
predictability of transmission shifts when pulling
a heavy trailer or a large or heavy load.
•
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
•
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
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