GMC SIERRA 2008 Owner's Manual

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 prep package, called
RPO VYU, 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.Some vehicles are built with a special snow plow prep
package, called RPO VYU. 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 Gross Vehicle Weight (GVW), are not exceeded.
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.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.
United States
Canada
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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.
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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 that have certain front
mounted equipment, such as a snow plow, it
may be possible to load the front axle to the
front gross axle weight rating (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.
CAUTION: (Continued)
CAUTION: (Continued)
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 gross vehicle weight
rating (GVWR). Maintaining a proper front and
rear weight distribution ratio is necessary to
provide proper braking performance.
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Total vehicle reserve capacity 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/retailer 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/retailer for additional advice and
information about using a snow plow on your vehicle.
Also, seeLoading Your Vehicle on page 4-36.
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 above the overhead console. SeeAuxiliary
Roof Mounted Lamp on page 3-20for switch location.
Truck-Camper Loading Information
A vehicle specic Truck-Camper Loading
information label is attached to the inside of your
vehicle’s glove box. This label 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 the 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 the following:
Everything else added to the camper after it
left the factory
Everything in the camper
All the people inside
The Cargo Weight Rating (CWR) is the maximum
weight of the load your vehicle can carry. It
does not include the weight of the people inside.
But, you can gure about 150 lbs (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 the glove box for dimensions A and
B as shown in the following illustration.
Use the rear edge of the load oor 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
When the truck is used to carry a slide-in camper,
the total cargo load of the truck consists of the
manufacturer’s camper weight gure, the weight of
installed additional camper equipment not
included in the manufacturer’s camper weight
gure, the weight of camper cargo, and the weight
of passengers in the camper. The total cargo
load should not exceed the truck’s cargo weight
rating and the camper’s center of gravity (A)
should fall within the truck’s recommended center
of gravity zone (B) when installed.
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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.
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 and help you determine the
CWR.
After you have 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 the axles. The loads on the front and rear
axles should not be more than either of the
Gross Axle Weight Ratings (GAWR). The total of
the axle loads should not be more than the
Gross Vehicle Weight Rating (GVWR).
Open the driver’s door and look at the
Certication/Tire label to nd out your vehicle’s
GAWRs and GVWR.
If your vehicle has gone over the weight ratings,
move or take out some things until all the
weight falls below the ratings.Secure loose items to prevent weight shifts that
could affect the balance of your vehicle. When the
truck-camper is loaded, drive to a scale and weigh
on the front and on the rear wheels separately to
determine axle loads. Individual axle loads should
not exceed either of the gross axle weight ratings
(GAWR). The total axle loads should not exceed
your vehicle’s gross vehicle weight rating (GVWR).
These ratings are given on the vehicle certication
label attached to the rear edge of the driver’s door.
See “Certication/Tire Label” underLoading Your
Vehicle on page 4-36. If weight ratings are
exceeded, move or remove items to bring all
weights below the ratings.
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.”
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Pickup Conversion to Chassis Cab
We are aware that some vehicle owners might consider
having the pickup box removed and a commercial or
recreational body installed. Owners should be aware
that, as manufactured, there are differences between a
chassis cab and a pickup with the box removed
which could affect vehicle safety. The components
necessary to adapt a pickup to permit its safe use
with a specialized body should be installed by the
body builder.
Towing
Towing Your Vehicle
Consult your dealer/retailer or a professional towing
service if you need to have your disabled vehicle towed.
SeeRoadside Assistance Program on page 7-7.
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
will 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”.
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing” following.
Here are some important things to consider before you
do recreational vehicle towing:
What’s the towing capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they can tow.
Do you have the proper towing equipment?
See your dealer or trailering professional for
additional advice and equipment recommendations.
Is your vehicle ready to be towed? Just as you
would prepare your vehicle for a long trip, you’ll
want to make sure your vehicle is prepared to be
towed. SeeBefore Leaving on a Long Trip on
page 4-29.
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Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If you tow your vehicle with all four wheels
on the ground, the drivetrain components could
be damaged. The repairs would not be covered by
your warranty. Do not tow your vehicle with all
four wheels on the ground.
Two-wheel-drive vehicles should not be towed with all
four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
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4. Securely attach the vehicle being towed to the tow
vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in PARK (P).
You or others could be injured. Make sure the
parking brake is rmly set before you shift the
transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-36for the proper
procedure to select the neutral position for
your vehicle.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
7. Turn the ignition to LOCK/OFF.
Dolly Towing
Front Towing (Front Wheels Off the
Ground)
Two-Wheel-Drive Vehicles
Notice:If you tow a two-wheel-drive vehicle with
the rear wheels on the ground, the transmission
could be damaged. The repairs would not be
covered by your warranty. Never tow your vehicle
with the rear wheels on the ground.
Two-wheel-drive vehicles should not be towed with the
rear wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
To dolly tow a two-wheel-drive vehicle, you must tow
the vehicle with the rear wheels on the dolly. See “Rear
Towing (Rear Wheels Off the Ground)” later in this
section for more information.
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