2003 GMC SIERRA DENALI Owners Manual

Add-on Equipment
When you carry removable items, you may need to put
a limit on how many people you carry inside your
vehicle. Be sure to weigh your vehicle before you buy
and install the new equipment.
Notice: Your warranty does not cover parts or
components that fail because of overloading.
Remember not to exceed the Gross Axle Weight Rating
(GAWR) of the front
or rear axle.
1 *EauiDment I Maximum Weiaht I .. I
Ladder Rack and Cargo I750 Ibs. (340 kg)
v
I Cross Toolbox and Carqo I400 Ibs. (181 kq) I
I
Side Boxes and Cargo 250 Ibs. per side (1 13 kg
I per side)
*The combined weight for all rail-mounted equipment
should not exceed
1,000 Ibs. (454 kg). A
reinforcement kit for rail-mounted add-on equipment is
recommended. See your dealer.
Truck-Camper Loading Information
This label is inside your glove box. It will tell you if
your vehicle can carry a slide-in camper, how much of a
load your vehicle can carry, and how
to correctly
spread out your load. Also, it will help you match the
right slide-in camper
to your vehicle.
When you carry a slide-in camper, the total cargo load
of your vehicle is the weight of the camper, plus
everything else added to the camper after it left the
factory,
everything in the camper and
all the people inside.
The Cargo Weight Rating (CWR) is the maximum
weight of the load your vehicle can carry.
It doesn’t
include the weight of the people inside. But, you
can figure about
150 Ibs. (68 kg) for each seat.
The total cargo load must not be more than your
vehicle’s CWR.
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Refer to the Truck-Camper Loading Information label in
glove box for dimensions
A and B as shown in the
following illustration.
Use the rear edge
of the load floor for measurement
purposes. The recommended location for the cargo
center
of gravity is at point C for the CWR. It is the point
where the mass of a body is concentrated and,
if
suspended at that point, would balance the front and rear. Here
is an example of proper truck and camper match:
A. Camper Center of Gravity
B. Recommended Center of Gravity Location Zone
The camper’s center
of gravity should fall within
the center of gravity zone for your vehicle’s cargo load.
You must weigh any accessories or other equipment
that you add to your vehicle. Then, subtract this
extra weight from the CWR. This extra weight may
shorten the center
of gravity zone of your vehicle. Your
dealer can help you with this.
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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.
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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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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/HauI 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.
Your vehicle may be equipped with a switch at the end
of the shift lever which when pressed enables
tow/haul. When the switch is pressed, a light on the
instrument panel will illuminate to indicate that tow/haul
has been selected. Tow/haul may be turned
off by
pressing the switch again, at which time the indicator
light on the instrument panel will turn
off. The vehicle will
automatically turn
off tow/haul every time it is started.
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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 this section.
Tow/haul
is most useful under the following driving
conditions:
When pulling a heavy trailer or a large or heavy
When pulling a heavy trailer or a large or heavy
load
through rolling terrain.
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.
Weight of the Trailer
How heavy can a trailer safely be?
It depends
on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
Use one of the following charts to determine how
much your vehicle can weigh, based upon your vehicle
model and options.
Maximum trailer weight is calculated assuming only the
driver is in the tow vehicle and it has all the required
trailering equipment. The weight
of additional optional
equipment, passengers and cargo in the tow vehicle
must be subtracted from the maximum trailer weight.
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**Maximum Trailer Weight 9,200 Ibs for fifth-wheel or gooseneck.
The Gross Combination Weight Rating (GCWR) is the
total allowable weight of the completely loaded
vehicle and trailer including any passengers, cargo,
equipment and conversions. The GCWR for your vehicle
should not be exceeded.
You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in
your Warranty and Owner Assistance Information
Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre,
163-005
1908 Colonel Sam Drive
Oshawa. Ontario L1
H 8P7
Weight of Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. And
if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle will be
carrying that weight, too. See
Loading Your Vehicle
on page
4-45 for more information about your vehicle’s
maximum load capacity.
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A B
If you’re using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight
(A) should be 10 percent
to
15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
After you’ve loaded your trailer, weigh the trailer and
then the tongue, separately, to see
if the weights
are proper. If they aren’t, you may be able to get them
right simply by moving some items around in the
trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the upper limit
for cold tires. You’ll find these numbers on the
Certificationnire label at the rear edge of the driver’s
door or see
Loading Your Vehicle on page 4-45.
Then be sure you don’t go over the GVW or rear axle
limit for your vehicle, including the weight of the
trailer tongue.
If you use a weight distributing hitch,
make sure you don’t go over the rear axle limit before
you apply the weight distribution spring.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you’ll need the right hitch, Here
are some rules to follow:
0 If you’ll 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 you’re driving.
4-55