2008 GMC SIERRA wheel

To prevent transmission wear, wait until the wheels stop
spinning before shifting gears. Release the accelerator
pedal while you shift, and press lightly on the accelerator
pedal when the transmission is in gear. By slowly
spinning the wheels in the forward and reverse
directions, you will cause a rocking motion that could
free your vehicle. If that does not get your vehicle
out after a few tries, it might need to be towed out.
Or, you can use recovery hooks, if your vehicle
has them. If your vehicle does need to be towed out,
seeTowing Your Vehicle on page 4-50.
Recovery Hooks
{CAUTION:
These hooks, when used, are under a lot of
force. Always pull the vehicle straight out.
Never pull on the hooks at a sideways angle.
The hooks could break off and you or others
could be injured from the chain or cable
snapping back.Notice:Never use recovery hooks to tow the
vehicle. Your vehicle could be damaged and it would
not be covered by warranty.
For vehicles with recovery hooks at the front of the
vehicle, you can use them if you are stuck off-road and
need to be pulled to some place where you can
continue driving.
4-35

Two-Tiered Loading
Depending on the model of your pick-up, you can
create an upper load platform by positioning
two or four 2 inches (5 cm) by 6 inches (15 cm)
wooden planks across the width of the pickup box.
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
Cargo750 lbs (340 kg)
Cross Toolbox and
Cargo400 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).
4-42

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.
4-45

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.”
4-49

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.
4-50

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.
4-51

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.
4-52

Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Drive the vehicle up onto the tow dolly.
2. Shift the transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to the
tow dolly.
{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.
6. 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.
7. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
8. Turn the ignition to LOCK/OFF.
4-53