2003 GMC SIERRA DENALI towing

Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE
(R) and a forward gear,
spinning the wheels as little as possible. Release
the accelerator pedal while you shift, and press lightly
on the accelerator pedal when the transmission is
in gear. By slowly spinning your wheels in the forward
and reverse directions, you will cause a rocking
motion that may free your vehicle.
If that doesn’t get
you out after a few tries, you may need to be towed out.
Or, you can use your recovery hooks
if your vehicle
has them.
If you do need to be towed out, see Towing
Your Vehicle on page 4-45.
Using the Recovery Hooks
I
Your vehicle is equipped with recovery hooks. The
hooks are provided at the front of your vehicle. You may
need to use them
if you’re stuck off-road and need to
be pulled to some place where you can continue driving.
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Towing Loading Your Vehicle
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Assistance Program on page 7-5.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle
- such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing” (towing your
vehicle with all four wheels on the ground) and “dolly
towing” (towing your vehicle with two wheels on
the ground and two wheels up on a device known
as a
“dolly”).
Your vehicle was not designed to be towed with any of
its wheels on the ground. If your vehicle must be
towed, see
Towing Your Vehicle on page 4-45.
Notice: Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two
of
its wheels on the ground, will damage drivetrain
components. Don’t tow an all-wheel-drive vehicle if
any
of its wheels will be on the ground.
COLD TIRE PRESSURE
00
The Certificationflire label is found on the rear edge of
the driver’s door.
The label shows the size of your original tires and the
inflation pressures needed to obtain the gross weight
capacity of your vehicle. This is called the GVWR (Gross
Vehicle Weight Rating). The GVWR includes the
weight of the vehicle, all occupants, fuel and cargo.
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If your slide-in camper and its load weighs less than the
CWR, the center of gravity zone for your vehicle may
be larger.
Your dealer can help you make a good vehicle-camper
match. He’ll also help you determine your CWR.
After you’ve loaded your vehicle and camper, drive
to a
weigh station and weigh the front and rear wheels
separately. This will tell you the loads on your axles.
The loads on the front and rear axles shouldn’t be more
than either of the GAWRs. The total of the axle loads
should not be more than the GVWR.
Open your driver’s door and look at the Certification/Tire
label to find out your GAWR and GVWR.
If you’ve gone over your weight ratings, move or take
out some things until all the weight falls below the
ratings. Of course, you should always tie down any
loose items when you load your vehicle or camper.
When you install and load your slide-in camper, check
the manufacturer’s instructions.
If you want more information on curb weights, cargo
weights, Cargo Weight Rating and the correct center of
gravity zone for your vehicle, your dealer can help
you. Just ask for a copy of ”Consumer Information,
Truck-Camper Loading.”
Trailer Recommendations
You must subtract your hitch loads from the CWR for
your vehicle. Weigh your vehicle with the trailer
attached, so that you won’t go over the GVWR or
GAWR.
If you are using a weight-distributing hitch,
weigh the vehicle without the spring bars in place.
You’ll get the best performance
if you spread out the
weight of your load the right way, and
if you choose the
correct hitch and trailer brakes.
For more information, see ”Trailer Towing” in the Index.
Pickup Conversion to
Chassis Cab
General Motors is aware that some vehicle owners may
consider having the pickup box removed and
a
commercial or recreational body installed. Before you do
so, first contact GM Customer Assistance for information
on such conversions specific to this vehicle. Owners
should be aware that, as manufactured, there are
differences between a chassis cab and a pickup with
the box removed which may affect vehicle safety.
The components necessary
to adapt a pickup to permit
its safe use with a specialized body should be
installed by a body builder in accordance with the
information available from GM Customer Assistance.
See
Customer Assistance Offices on page 7-4.
4-50

Towing a Trailer
If you don’t ,se the correct eq-., ...__. t and
drive properly, you can lose control when you
pull a trailer. For example,
if the trailer is too
heavy, the brakes may not work well
-- or even
at all. You and your passengers could be
seriously injured.
Pull a trailer only if you have
followed all the steps in this section.
Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice: Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered
by your warranty.
To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer with
your vehicle. Additional rear axle maintenance is required for a vehicle used to tow a trailer. See
“Scheduled Maintenance Services” in the Index.
To identify the vehicle trailering capacity of your vehicle,
you should read the information in “Weight of the
Trailer” that appears later in this section.
If yours was built with trailering options, as many are,
it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, durability and fuel economy.
Successful, safe trailering takes correct equipment, and it has to be used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers.
So please read this section carefully before
you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
e
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
if your trailer will
weigh
5,000 Ibs. (2 270 kg) or less. You should
always use a sway control
if your trailer will weigh
more than
5,000 Ibs. (2 270 kg). You can ask a
hitch dealer about sway controls.
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.
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Safety Chains
You should always attach safety 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.
You may attach the safety chains to the attaching point
on the hitch platform. 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 Ibs. (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:
(20 650 kPa) of pressure.
The trailer parts can withstand 3,000 psi
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid 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 fluid
to the rear brakes. But don’t use copper tubing for this.
If you do, it will bend and finally break off. Use steel
brake tubing.
Driving with a Trailer
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.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be
sure the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
While towing a trailer or when exposed to long periods
of sunshine, the floor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
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Making Turns
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good deal
longer, you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and,
if possible,
have someone guide you.
Your vehicle is equipped with four-wheel steering and
if
you use it while backing your trailer the same rules
apply. However, with four-wheel steering your rig will
respond more quickly and it may take additional practice
to get used to backing up with four-wheel steering.
Notice: Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns
than normal.
Do this so your trailer won’t strike
soft shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also flash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even
if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
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Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade.
If you don’t shift
down, you might have to use your brakes
so much that
they would get hot and no longer work well.
You can tow in DRIVE
(5). 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).
You may also want to activate the tow/haul mode
if the
transmission shifts too often. See “Tow/Haul Mode”
earlier in this section.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes.
If you turn your
engine
off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar
to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) for a
few minutes before turning the engine
off. If you do get
the overheat warning, see
Engine Overheating on
page
5-27.
Parking on Hills
m
You really should not park your vehicle, with a
trailer attached, on a hill.
If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK
(P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
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When You Are Ready to Leave After
Parking on a
Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 start your engine,
shift into a gear, and
0 release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t overfill),
engine
oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you find 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.
4-59