2005 GMC SIERRA 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 pounds” 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 kilograms or XXX pounds.
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 4-68for
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)
CAvailable 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=1,000 lbs (453 kg)
CAvailable 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.
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 4-56.{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.
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{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’ll keep going.
{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’s also important loading information for off-road
driving in this manual. See “Loading Your Vehicle
for Off-Road Driving“ underOff-Road Driving with Your
Four-Wheel-Drive Vehicle on page 4-20.
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Two-Tiered Loading
By positioning four 2” x 6” 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.
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’ 8” 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 5’8” pick-up box length.) Maximum
recommended cross-mounted toolbox and cargo
weight is 300 lbs (136 kg) for the 1500 crew cab
(with 5’8” pick-up box length.)
4-55

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 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.
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.
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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.
Q:What is front axle reserve capacity, and how do
I calculate it?
A:Front axle reserve capacity is the difference
between your front GAWR and the front axle weight
of your truck 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.
United States
Canada
4-57

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 WheelbaseFor 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 GVWR must never be exceeded.
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