GMC SIERRA 2006 Owner's Manual

There is also important loading information on the vehicle
Certication/Tire label. It tells you the Gross Vehicle
Weight Rating (GVWR) and the Gross Axle Weight
Rating (GAWR) for the front and rear axles. See
“Certication/Tire Label” later in this section.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined weight
of occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle’s placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and
passengers from XXX kg or XXX lbs.
4. The resulting gure equals the available amount of
cargo and luggage load capacity. For example, if the
“XXX” amount equals 1400 lbs and there will be
ve 150 lb passengers in your vehicle, the amount
of available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5. Determine the combined weight of luggage and
cargo being loaded on the vehicle. That weight
may not safely exceed the available cargo
and luggage load capacity calculated in Step 4.6. If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage load
capacity of your vehicle. SeeTowing a Trailer
on page 4-67for important information on towing
a trailer, towing safety rules and trailering tips.
Item Description Total
AVehicle Capacity Weight
for Example 1=1,000 lbs (453 kg)
BSubtract Occupant
Weight
150 lbs (68 kg)×2=300 lbs (136 kg)
CAvailable Occupant and
Cargo Weight=700 lbs (317 kg) Example 1
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Item Description Total
AVehicle Capacity Weight
for Example 2=1,000 lbs (453 kg)
BSubtract Occupant
Weight
150 lbs (68 kg)×5=750 lbs (136 kg)
C Available Cargo Weight=250 lbs (113 kg)Item Description Total
AVehicle Capacity Weight
for Example 3=1,000 lbs (453 kg)
BSubtract Occupant
Weight
200 lbs (91 kg)×5=1000 lbs (453 kg)
C Available Cargo Weight=0 lbs (0 kg)
Refer to your vehicle’s tire and loading information label
for specic information about your vehicle’s capacity
weight and seating positions. The combined weight of the
driver, passengers, and cargo should never exceed your
vehicle’s capacity weight. Example 2
Example 3
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Certication/Tire Label
A vehicle specic Certication/Tire label is found on
the rear edge of the driver’s door. The label shows the
size of your vehicle’s original tires and the ination
pressures needed to obtain the gross weight capacity
of your vehicle. This is called Gross Vehicle Weight
Rating (GVWR). The GVWR includes the weight of
the vehicle, all occupants, fuel, and cargo.The Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR). To nd out the actual loads on
your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help you
with this. Be sure to spread out your load equally on both
sides of the centerline.
Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
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The Certication/Tire label also contains important
information about your Front Axle Reserve Capacity.
See “What is front axle reserve capacity, and how do
I calculate it?” underAdding a Snow Plow or Similar
Equipment on page 4-54.
{CAUTION:
In the case of a sudden stop or collision,
things carried in the bed of your truck could
shift forward and come into the passenger
area, injuring you and others. If you put things
in the bed of your truck, you should make sure
they are properly secured.
{CAUTION:
Do not load your vehicle any heavier than the
Gross Vehicle Weight Rating (GVWR), or either
the maximum front or rear Gross Axle Weight
Rating (GAWR). If you do, parts on your vehicle
can break, and it can change the way your
vehicle handles. These could cause you to
lose control and crash. Also, overloading can
shorten the life of your vehicle.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask your
dealer to help you load your vehicle the right way.
If you put things inside your vehicle — like suitcases,
tools, packages, or anything else — they go as fast
as the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they will keep going.
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{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There is also important loading information for off-road
driving in this manual. See “Loading Your Vehicle
for Off-Road Driving“ underOff-Road Driving on
page 4-16.
Two-Tiered Loading
By positioning four 2 inches (5 cm) by 6 inches (15 cm)
wooden planks across the width of the pickup box,
you can create an upper load platform. The planks
must be inserted in the pickup box depressions.
The length of the planks must allow for at least a
3/4 inch (2 cm) bearing surface on each end of
the plank.
When using this upper load platform, be sure the load is
securely tied down to prevent it from shifting. The load’s
center of gravity should be positioned in a zone over the
rear axle. The zone is located in the area between the
front of each wheel well and the rear of each wheel well.
The center of gravity height must not extend above the
top of the pickup box areboard.
Any load that extends beyond the vehicle’s taillamp
area must be properly marked according to local laws
and regulations.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
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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:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Remember not to exceed the Gross Axle Weight Rating
(GAWR) of the front or rear axle.
*Equipment Maximum Weight
Ladder Rack and Cargo 750 lbs (340 kg)
Cross Toolbox and Cargo 400 lbs (181 kg)
Side Boxes and Cargo 250 lbs per side
(113 kg per side)
*The combined weight for all rail-mounted equipment
should not exceed 1,000 lbs (454 kg), excluded
1500 crew cab models with 5 ft 8 in (173 cm) box
length. A reinforcement kit for rail-mounted add-on
equipment is recommended. See your dealer.
Ladder racks are not recommended for 1500 crew
cab models with 5 ft 8 in (173 cm) pick-up box length.
Maximum recommended cross-mounted toolbox and
cargo weight is 300 lbs (136 kg) for the 1500 crew
cab with 5 ft 8 in (173 cm) pick-up box length.
Adding a Snow Plow or Similar
Equipment
Before installing a snow plow on your vehicle, here are
some things you will need to know:
Notice:If your vehicle does not have the snow
plow prep package, adding a plow can damage
your vehicle, and the repairs would not be covered
by warranty. Unless your vehicle was built to carry
a snow plow, do not add one to your vehicle. If
your vehicle has the snow plow option called RPO
VYU (snow plow prep package), then the payload
your vehicle can carry will be reduced when a snow
plow is installed. Your vehicle can be damaged if
either the front or rear axle ratings or the gross
vehicle weight (GVW) are exceeded.
Q:How do I know if my vehicle can handle a
snow plow?
A:Some vehicles are built with a special package,
called RPO VYU (snow plow prep package). If your
vehicle has this option, you can add a plow to it,
provided certain weights, such as the weights on
the vehicle’s axles and the GVW, are not exceeded.
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Q:How heavy can a snow plow safely be?
A:The plow your vehicle can carry depends on many
things, such as:
The options your vehicle came with, and the weight
of those options.
The weight and number of passengers you intend
to carry.
The weight of items you have added to your
vehicle, like a tool box or truck cap.
The total weight of any additional cargo you intend
to carry.
Say, for example, you have a 700 lb (318 kg) snow plow.
The total weight of all occupants and cargo inside the cab
should not exceed 300 lb (135 kg). This means that you
may only be able to carry one passenger. But, even this
may be too much if you have got other equipment already
adding to the weight of your vehicle.Here are some guidelines for safely carrying a snow
plow on your vehicle:
Make sure the weight on the front and rear axles
does not exceed the axle rating for each.
For the front axle, if more cargo or passengers must
be carried, appropriate counter ballast must be
installed rear of the rear axle. Counter ballast must
be properly secured so it will not move during driving.
Follow the snow plow manufacturer’s
recommendations regarding rear ballast. Rear
ballast may be required to ensure a proper front and
rear weight distribution ratio, even though the actual
weight at the front axle may be less than the front
axle rating.
The snow plow manufacturer or installer can
assist you in determining the amount of rear ballast
required, to help make sure your snowplow/vehicle
combination does not exceed the GVW rating, the
front and rear axle ratings, and the front and rear
weight distribution ratio.
The total vehicle must not exceed the GVW rating.
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Q:What is front axle reserve capacity, and how do
I calculate it?
A:Front axle reserve capacity is the difference
between your front gross axle weight rating (GAWR)
and the front axle weight of your vehicle with full
fuel and passengers. Basically, it is the amount
of weight you can add to your front axle before
reaching your front GAWR.
The front axle reserve capacity for your vehicle can be
found in the lower right corner of the Certication/Tire
label, as shown.In order to calculate the amount of weight any front
accessory, such as a snow plow, is adding to the front
axle, use the following formula:
(W x (A + W.B.)) /W.B.= Weight the accessory is adding
to the front axle.
Where:
W = Weight of added accessory
A = Distance that the accessory is in front of the
front axle
W.B. = Vehicle Wheelbase United States
Canada
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For example, adding a 700 lb (318 kg) snow plow
actually adds more than 700 lbs (318 kg) to the front
axle. Using the formula, if the snow plow is 4 ft (122 cm)
in front of the front axle and the wheel base is
10 ft (305 cm), then:
W = 700 lb (318 kg)
A = 4 ft (122 cm)
W.B. = 10 ft (305 cm)
(W x (A + W.B.))/W.B. = (700 x (4 + 10))/10 = 980 lbs
(445 kg)
So, if your truck’s front axle reserve capacity is more
than 980 lbs (445 kg), you could add the snow plow
without exceeding the front GAWR.
Q:What if I want to add heavier equipment to my
vehicle?
A:You can add heavier equipment on the front of the
vehicle if you compensate for it by carrying fewer
passengers, less cargo, or by positioning cargo
towards the rear. This has the effect of reducing
the load on the front. However, the front GAWR,
rear GAWR and the gross vehicle weight
rating (GVWR) must never be exceeded.
{CAUTION:
On some vehicles equipped with certain front
mounted equipment, such as a snow plow, it
may be possible to load the front axle to the
front GAWR but not have enough weight on the
rear axle to have proper braking performance.
If your brakes can not work properly, you could
have a crash. To help your brakes work properly
when a snow plow is installed, always follow
the snow plow manufacturer or installer’s
recommendation for rear ballast to ensure a
proper front and rear weight distribution ratio,
even though the actual front weight may be
less than the front GAWR, and the total vehicle
weight is less than the GVWR. Maintaining a
proper front and rear weight distribution ratio
is necessary to provide proper braking
performance.
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Q:What is total vehicle reserve capacity?
A:This is the difference between your GVWR and the
weight of your truck with full fuel and passengers.
It is the amount of weight you can add to your vehicle
before reaching your GVWR. Keep in mind that
reserve capacity numbers are intended as a guide
when selecting the amount of equipment or cargo
your truck can carry. If you are unsure of your
vehicle’s front, rear, or total weight, go to a weigh
station and weigh your vehicle. Your dealer can also
help you with this.
The total vehicle reserve capacity for your vehicle
can be found in the lower right corner of the
Certication/Tire label as shown previously.
See your dealer for additional advice and information
about using a snow plow on your vehicle. Also, see
Loading Your Vehicle on page 4-48.
Emergency Roof Lamp Provisions
Vehicles with the RPO VYU snow plow prep package
also have an emergency roof lamp provision package,
RPO TRW. Wiring for the emergency roof lamp is
provided in the B-pillar as shown. SeeAuxiliary Roof
Mounted Lamp on page 3-18for switch location.
A. Body Side Inner Panel
B. Emergency Roof Lamp Harness
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