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All Other Models
A. Stoplamp/Taillamp/Turn Signal Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
C. Back-up Lamp
D. Sidemarker Lamp
5. Pull the old bulb straight out from the socket.
6. Press a new bulb into the socket and turn the socket clockwise into the taillamp assembly.
7. Reinstall the taillamp assembly.
Taillamps (Chassis Cab Models)
A. Backup Lamp
B. Stoplamp/Taillamp/Turn Signal Lamp
To replace one of these bulbs: 1. Remove the four screws.
2. Lift the lens off the lamp assembly.
3. Turn the old bulb counterclockwise and pull the it straight out from the socket.
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4. Install a new bulb into the socket, turn it clockwise,and press it in until it is tight.
5. Reinstall the lens and the four screws.
License Plate Lamp
To replace one of these bulbs: 1. Reach under the rear bumper for the bulb socket.
2. Turn the bulb socket counterclockwise and pull the bulb socket out of the connector.
3. Pull the old bulb from the bulb socket, keeping the bulb straight as you pull it out.
4. Install the new bulb.
5. Reverse Steps 1 through 3 to reinstall the bulb socket.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 3047 or 921
Back-up Lamp* 1156
Cargo Lamp and Center
High-Mounted Stoplamp (CHMSL) 912
Fender Marker Lamp W5WLL
High-Beam Headlamp 9005
Low-Beam Headlamp H11
License Plate Lamp 168
Sidemarker Lamp/Stoplamp/Taillamp/
Turn Signal Lamp 3047
Stoplamp/Turn Signal Lamp/Taillamp* 1157
* Chassis Cab Models
For replacement bulbs not listed here, contact your
dealer.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenanceon page 7‑3for more information on wiper blade inspection.
Replacement blades come in different types and are
removed in different ways. Here is how to remove the
wiper blade:
1. Pull the windshield wiper arm connector away from the windshield.
2. Squeeze the grooved areas on each side of theblade and turn the blade assembly away from the
arm connector.
3. Install the new blade onto the arm connector and
make sure the grooved areas are fully set in the
locked position.
For the proper type and size, see Maintenance
Replacement Parts on page 7‑15.
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Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and
where to obtain service, see your vehicle
Warranty booklet for details. For additional
information refer to the tire manufacturer.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
.Overloading your vehicle's tires can
cause overheating as a result of too
much flexing. You could have an air-out
and a serious accident. SeeLoading the
Vehicle
on page 5‑29.
.Underinflated tires pose the same danger
as overloaded tires. The resulting
accident could cause serious injury.
Check all tires frequently to maintain the
recommended pressure. Tire pressure
(Continued)
CAUTION: (Continued)
should be checked when your vehicle's
tires are cold. See Inflation - Tire
Pressure
on page 6‑73.
.Overinflated tires are more likely to be
cut, punctured, or broken by a sudden
impact —such as when you hit a pothole.
Keep tires at the recommended pressure.
.Worn, old tires can cause accidents.
If the tire's tread is badly worn, or if your
vehicle's tires have been damaged,
replace them.
20‐Inch Tires
If your vehicle has the optional 20‐inch P275/
55R20 size tires, they are classified as touring
tires and are designed for on road use. The low‐
profile, wide tread design is not recommended for
“off‐road” driving or commercial uses such as
snow plowing. See Off-Road Driving
on page 5‑11
andAdding a Snow Plow or Similar Equipmenton
page 5‑37
for additional information.
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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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(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) 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.
(D) 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. (E) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under the
tread.
(F) Uniform Tire Quality Grading (UTQG)
:Tire
manufacturers are required to grade tires based
on three performance factors: treadwear, traction,
and temperature resistance. For more information,
see Uniform Tire Quality Grading
on page 6‑85.
(G) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.
For information on recommended tire pressure
see Inflation - Tire Pressure
on page 6‑73and
Loading the Vehicle
on page 5‑29.
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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 6‑73
and Loading the Vehicleon page 5‑29.
(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 6‑73
andLoading the Vehicleon page 5‑29.
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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