2007 GMC SIERRA CLASSIC ESP

Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is
safe and close to home before you go into
the wilderness. Off-road driving does require
some new and different driving skills. Here is
what we mean.
Tune your senses to different kinds of signals.
Your eyes, for example, need to constantly sweep
the terrain for unexpected obstacles. Your ears
need to listen for unusual tire or engine sounds.
With your arms, hands, feet, and body, you
will need to respond to vibrations and vehicle
bounce.
Controlling your vehicle is the key to successful
off-road driving. One of the best ways to
control your vehicle is to control your speed.Here are some things to keep in mind. At higher
speeds:You approach things faster and you have less
time to scan the terrain for obstacles.
You have less time to react.
You have more vehicle bounce when you
drive over obstacles.
You will need more distance for braking,
especially since you are on an unpaved
surface.
{CAUTION:
When you are driving off-road, bouncing
and quick changes in direction can easily
throw you out of position. This could cause
you to lose control and crash. So, whether
you are driving on or off the road, you and
your passengers should wear safety belts.
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When you drive over bumps, rocks, or other
obstacles, your wheels can leave the ground.
If this happens, even with one or two wheels,
you cannot control the vehicle as well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
In a way, off-road driving requires a different kind
of alertness from driving on paved roads and
highways. There are no road signs, posted speed
limits, or signal lights. You have to use your
own good judgment about what is safe and what
is not.
Drinking and driving can be very dangerous on
any road. And this is certainly true for off-road
driving. At the very time you need special alertness
and driving skills, your reexes, perceptions,
and judgment can be affected by even a small
amount of alcohol. You could have a serious — or
even fatal — accident if you drink and drive or
ride with a driver who has been drinking.
SeeDrunken Driving on page 357.Driving on Off-Road Hills
Off-road driving often takes you up, down, or
across a hill. Driving safely on hills requires good
judgment and an understanding of what your
vehicle can and cannot do. There are some hills
that simply cannot be driven, no matter how
well built the vehicle.
{CAUTION:
Many hills are simply too steep for any
vehicle. If you drive up them, you will stall.
If you drive down them, you cannot control
your speed. If you drive across them, you
will roll over. You could be seriously
injured or killed. If you have any doubt
about the steepness, do not drive the hill.
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After Off-Road Driving
Remove any brush or debris that has collected
on the underbody, chassis, or under the hood.
These accumulations can be a re hazard.
After operation in mud or sand, have the brake
linings cleaned and checked. These substances
can cause glazing and uneven braking. Check the
body structure, steering, suspension, wheels,
tires, and exhaust system for damage. Also, check
the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service
due to off-road use. Refer to the Maintenance
Schedule for additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to
be impaired — by alcohol or drugs, with night
vision problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
Since you cannot see as well, you may need
to slow down and keep more space between
you and other vehicles.
Slow down, especially on higher speed roads.
Your vehicle’s headlamps can light up only so
much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe
place and rest.
No one can see as well at night as in the daytime.
But as we get older these differences increase.
A 50-year-old driver may require at least twice as
much light to see the same thing at night as a
20-year-old.
What you do in the daytime can also affect your
night vision. For example, if you spend the
day in bright sunshine you are wise to wear
sunglasses. Your eyes will have less trouble
adjusting to night. But if you are driving, do not
wear sunglasses at night. They may cut down on
glare from headlamps, but they also make a
lot of things invisible.
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Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong
forces. If you try to drive through owing
water, as you might at a low water
crossing, your vehicle can be carried
away. As little as six inches of owing
water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown. Do not ignore
police warning signs, and otherwise be
very cautious about trying to drive
through owing water.
Some Other Rainy Weather Tips
Turn on your low-beam headlamps — not just
your parking lamps — to help make you more
visible to others.
Besides slowing down, allow some extra
following distance. And be especially
careful when you pass another vehicle.
Allow yourself more clear room ahead, and
be prepared to have your view restricted
by road spray.
Have good tires with proper tread depth.
SeeTires on page 543.
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You can run the engine to keep warm, but be
careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see
it or smell it, so you might not know it is in
your vehicle. Clear away snow from around
the base of your vehicle, especially any
that is blocking your exhaust pipe. And
check around again from time to time to
be sure snow does not collect there.
Open a window just a little on the side of
the vehicle that is away from the wind.
This will help keep CO out.
Run your engine only as long as you must.
This saves fuel. When you run the engine, make it
go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat
that you get and it keeps the battery charged.
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The hitch should be located in the pickup bed so
that it’s centerline is over or slightly in front of the
rear axle. Take care that it is not so far forward that
it will contact the back of the cab in sharp turns.
This is especially important for short box pickups.
Trailer pin box extensions and sliding fth wheel
hitch assemblies can help this condition. There
should be at least six inches of clearance between
the top of the pickup box and the bottom of the
trailer shelf that extends over the box.
Make sure the hitch is attached to the tow vehicle
frame rails. Do not use the pickup box for support.
Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety chains
under the tongue of the trailer to help prevent the
tongue from contacting the road if it becomes
separated from the hitch. Instructions about safety
chains may be provided by the hitch manufacturer
or by the trailer manufacturer. If you are towing a
trailer up to 5,000 lbs (2 271 kg) with a
factory-installed step bumper, you may attach the
safety chains to the attaching points on the bumper.
If you are towing a trailer up to your vehicle’s trailer
rating limit you may attach the safety chains to the
attaching point on the hitch platform. If you aretowing with an aftermarket hitch follow the trailer or
hitch manufacturer’s recommendation for attaching
safety chains. Always leave just enough slack so
you can turn with your rig. Never allow safety
chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 2,000 lbs (900 kg)
loaded, then it needs its own brakes – and they
must be adequate. Be sure to read and follow the
instructions for the trailer brakes so you’ll be
able to install, adjust and maintain them properly.
Your trailer brake system can tap into the
vehicle’s hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of uid from your
vehicle’s master cylinder. Otherwise,
both braking systems won’t work well. You
could even lose your brakes.
If everything checks out this far, make the brake tap
at the port on the master cylinder that sends the
uid to the rear brakes. But don’t use copper tubing
for this. If you do, it will bend and nally break off.
Use steel brake tubing.
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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and
you pull a trailer with your vehicle, carbon
monoxide (CO) could come into your
vehicle. You cannot see or smell CO. It
can cause unconsciousness or death. See
Engine Exhaust on page 174. To maximize
your safety when towing a trailer:
Have your exhaust system inspected
for leaks, and make necessary repairs
before starting on your trip.
Keep the rear-most windows closed.
CAUTION: (Continued)
CAUTION: (Continued)

If exhaust does come into your vehicle
through a window in the rear or
another opening, drive with your front,
main heating or cooling system on
and with the fan on any speed. This
will bring fresh, outside air into your
vehicle. Do not use the climate control
setting for maximum air because it
only recirculates the air inside your
vehicle. SeeClimate Control System
on page 230.
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself with the feel of handling and braking with
the added weight of the trailer. And always
keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as
responsive as your vehicle is by itself.
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Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. SeeScheduled
Maintenance (Gasoline Engine) on page 617for
more information. Things that are especially
important in trailer operation are automatic
transmission uid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system.
Each of these is covered in this manual, and
the Index will help you nd them quickly. If you’re
trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and
bolts are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following
wiring harnesses for towing a trailer or hauling
a slide-in camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups
have an eight-wire trailer towing harness.For vehicles not equipped with heavy duty
trailering, the harness is clipped to the vehicle’s
frame behind the spare tire mount. The harness
requires the installation of a trailer connector,
which is available through your dealer.
If your trailer is equipped with electric brakes, you
can get a jumper harness (electric trailer brake
control) with a trailer battery feed fuse from
your dealer.
If you need to tow a light-duty trailer with a
standard four-way round pin connector, you can
also get an adapter from your dealer.
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