2010 GMC SIERRA height

Servicing Your Airbag-Equipped
Vehicle
Airbags affect how the vehicle should be serviced.
There are parts of the airbag system in several places
around the vehicle. Your dealer/retailer and the service
manual have information about servicing the vehicle
and the airbag system. To purchase a service manual,
seeService Publications Ordering Information
on
page 8‑16.
{WARNING:
For up to 10 seconds after the ignition is turned off
and the battery is disconnected, an airbag can still
inflate during improper service. You can be injured
if you are close to an airbag when it inflates. Avoid
yellow connectors. They are probably part of the
airbag system. Be sure to follow proper service
procedures, and make sure the person performing
work for you is qualified to do so.
Adding Equipment to Your
Airbag-Equipped Vehicle
Q: Is there anything I might add to or change about the vehicle that could keep the airbags from
working properly?
A: Yes. If you add things that change your vehicle's
frame, bumper system, height, front end or side
sheet metal, they may keep the airbag system from
working properly. Changing or moving any parts of
the front seats, safety belts, the airbag sensing and
diagnostic module, steering wheel, instrument panel,
roof-rail airbag modules, ceiling headliner or pillar
garnish trim, overhead console, front sensors, side
impact sensors, rollover sensor module, or airbag
wiring can affect the operation of the airbag system.
In addition, the vehicle may have a passenger
sensing system for the right front passenger's
position, which includes sensors that are part of the
passenger's seat. The passenger sensing system
may not operate properly if the original seat trim is
replaced with non-GM covers, upholstery or trim,
or with GM covers, upholstery or trim designed for a
different vehicle. Any object, such as an aftermarket
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{WARNING:
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 5‑11.
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 flareboard.
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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Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specifications in
Capacities and Specifications on page 6‑126.
If the vehicle has rear drum brakes, they do not have
wear indicators, but if a rear brake rubbing noise is
heard, have the rear brake linings inspected
immediately. Rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. Drum brakes have an inspection hole to
inspect lining wear during scheduled maintenance.
When the front brake pads are replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced—for
example, when the brake linings wear down and new
ones are installed —be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change —for the
worse. The braking performance expected can change
in many other ways if the wrong replacement brake
parts are installed.
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4. At a wall, measure from the ground upward (A) tothe recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the vehicle at the height of the mark
in Step 4.
Notice: Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the
headlamp not being adjusted. This allows only the
beam of light from the headlamp being adjusted to
be seen on the flat surface.
7. Locate the vertical headlamp aiming screws, whichare under the hood near each headlamp assembly.
The adjustment screw can be turned with an
E8 Torx
®socket.
8. Turn the vertical aiming screw until the headlamp beam is aimed to the horizontal tape line. Turn it
clockwise or counterclockwise to raise or lower
the angle of the beam.
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Notice:If the vehicle has low‐profile tires, they
are more susceptible to damage from road
hazards or curb impact than standard profile
tires. Tire and/or wheel assembly damage can
occur when coming into contact with road
hazards like, potholes, or sharp edged objects,
or when sliding into a curb. The vehicle
warranty does not cover this type of damage.
Keep tires set to the correct inflation pressure
and, when possible avoid contact with curbs,
potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples
of a typical P‐Metric and a LT‐Metric tire sidewall.
Passenger (P‐Metric) Tire
(A) Tire Size:The tire size code is a combination
of letters and numbers used to define a particular
tire's width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
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Light Truck (LT-Metric) Tire
(A) Tire Size:The tire size code is a combination
of letters and numbers used to define a particular
tire's width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail. (B) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires designed
to GM's specific tire performance criteria have a
TPC specification code molded onto the sidewall.
GM's TPC specifications meet or exceed all
federal safety guidelines.
(C) Dual Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used in a dual
configuration. For information on recommended
tire pressure see Inflation - Tire Pressure
on
page 6‑72
and Loading the Vehicleon page 5‑30.
(D) DOT (Department of Transportation)
:
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(E) Tire Identification Number (TIN)
:The letters
and numbers following DOT code are the Tire
Identification Number (TIN). The TIN shows the
manufacturer and plant code, tire size, and date
the tire was manufactured. The TIN is molded
onto both sides of the tire, although only one side
may have the date of manufacture.
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(F) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the
tread.
(G) Single Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended tire
pressure see Inflation - Tire Pressure
on page 6‑72
andLoading the Vehicleon page 5‑30.
Tire Size
The following examples show the different parts of
a tire size.
Passenger (P‐Metric) Tire
(A) Passenger (P‐Metric) Tire:The United
States version of a metric tire sizing system. The
letter P as the first character in the tire size means
a passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association. (B) Tire Width
:The three‐digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio
:A two‐digit number that
indicates the tire height‐to‐width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the tire illustration, it would
mean that the tire's sidewall is 75 percent as high
as it is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the
letter D means diagonal or bias ply construction;
and the letter B means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of the wheel
in inches.
(F) Service Description
:These characters
represent the load index and speed rating of the
tire. The load index represents the load carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
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Light Truck (LT‐Metric) Tire
(A) Light Truck (LT‐Metric) Tire:The United
States version of a metric tire sizing system.
The letters LT as the first two characters in the
tire size means a light truck tire engineered to
standards set by the U.S. Tire and Rim
Association.
(B) Tire Width
:The three‐digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio
:A two‐digit number that
indicates the tire height‐to‐width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the light truck (LT‐Metric) tire
illustration, it would mean that the tire's sidewall is
75 percent as high as it is wide. (D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the
letter D means diagonal or bias ply construction;
and the letter B means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Load Range
:Load Range.
(G) Service Description
:The service description
indicates the load index and speed rating of
a tire. If two numbers are given as in the example,
120/116, then this represents the load index for
single versus dual wheel usage (single/dual).
The speed rating is the maximum speed a tire is
certified to carry a load.
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