2012 CHEVROLET SILVERADO wheel size

Black plate (40,1)Chevrolet Silverado Owner Manual - 2012
3-40 Seats and Restraints
If you have any questions
about this, you should contact
Customer Assistance before you
modify your vehicle. The phone
numbers and addresses for
Customer Assistance are in
Step Two of the Customer
Satisfaction Procedure in this
manual. SeeCustomer
Satisfaction Procedure
(U.S. and Canada) on page 13‑1
or Customer Satisfaction
Procedure (Mexico) on
page 13‑3.
If the vehicle has rollover
roof-rail airbags, see Different
Size Tires and Wheels on
page 10‑74 for additional
important information. Q: What if I added a snow plow?
Will it keep the airbags from
working properly?
A: We have designed our airbag
systems to work properly under
a wide range of conditions,
including snow plowing with
vehicles that have the optional
Snow Plow Prep Package
(RPO VYU). But do not change
or defeat the snow plow's
“tripping mechanism.” If you do,
it can damage your snow plow
and your vehicle, and it may
cause an airbag inflation. Q: Because I have a disability,
I have to get my vehicle
modified. How can I find out
whether this will affect my
airbag system?
A: If you have questions,
call Customer Assistance.
The phone numbers and
addresses for Customer
Assistance are in Step Two of
the Customer Satisfaction
Procedure in this manual.
See Customer Satisfaction
Procedure (U.S. and
Canada) on page 13‑1 or
Customer Satisfaction
Procedure (Mexico) on
page 13‑3.
In addition, your dealer and the
service manual have information
about the location of the airbag
sensors, sensing and diagnostic
module and airbag wiring.

Black plate (47,1)Chevrolet Silverado Owner Manual - 2012
Instruments and Controls 5-47
Object Detection System
Messages
PARK ASST BLOCKED SEE
OWNERS MANUAL
This message displays if there is
something interfering with the park
assist system. SeeUltrasonic
Parking Assist on page 9‑68 for
more information.
PARK ASSIST OFF
After the vehicle has been started,
this message displays to remind the
driver that the URPA system has
been turned off. Press the set/reset
button or the trip odometer reset
stem to acknowledge this message
and clear it from the DIC display.
To turn the URPA system back on,
see Ultrasonic Parking Assist on
page 9‑68.
SERVICE PARK ASSIST
This message displays if there is a
problem with the Ultrasonic Rear
Parking Assist (URPA) system.
Do not use this system to help you
park. See Ultrasonic Parking Assist
on page 9‑68 for more information.
See your dealer for service.
Ride Control System
Messages
SERVICE STABILITRAK
If the vehicle has StabiliTrak and
this message displays, it means
there may be a problem with the
StabiliTrak system. If you see this
message, try to reset the system.
Stop; turn off the engine for at least
15 seconds; then start the engine
again. If this message still comes
on, it means there is a problem.
You should see your dealer for
service. The vehicle is safe to drive;
however, you do not have the
benefit of StabiliTrak, so reduce
your speed and drive accordingly.
SERVICE TRACTION
CONTROL
If the vehicle has StabiliTrak, this
message displays when there is a
problem with the Traction Control
System (TCS). When this message
displays, the system will not limit
wheel spin. Adjust your driving
accordingly. See your dealer for
service. See StabiliTrak
®System on
page 9‑62 for more information.
STABILITRAK INITIALIZING
If the vehicle has StabiliTrak, this
message may come on if the
StabiliTrak system has not fully
initialized because of road
conditions or the incorrect tire size.
When the StabiliTrak system is fully
initialized, the message will turn off.
SeeStabiliTrak
®System on
page 9‑62 for more information.
If this message continues to be
displayed for multiple ignition cycles
and on different road surfaces,
see your dealer for service.

Black plate (2,1)Chevrolet Silverado Owner Manual - 2012
10-2 Vehicle Care
Electrical System
Electrical SystemOverload . . . . . . . . . . . . . . . . . . 10-46
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-47
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . 10-47
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-51
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-54
Tire Sidewall Labeling . . . . . . 10-55
Tire Designations . . . . . . . . . . . 10-57
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-59
Tire Pressure . . . . . . . . . . . . . . . 10-62
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . 10-63
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-64
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-65
Tire Inspection . . . . . . . . . . . . . . 10-68
Tire Rotation . . . . . . . . . . . . . . . 10-69
Dual Tire Rotation . . . . . . . . . . 10-71
When It Is Time for New Tires . . . . . . . . . . . . . . . . . 10-71 Buying New Tires . . . . . . . . . . . 10-72
Different Size Tires and
Wheels . . . . . . . . . . . . . . . . . . . 10-74
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 10-74
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . 10-76
Wheel Replacement . . . . . . . . 10-77
Tire Chains . . . . . . . . . . . . . . . . . 10-78
If a Tire Goes Flat . . . . . . . . . . 10-79
Tire Changing . . . . . . . . . . . . . . 10-80
Full-Size Spare Tire . . . . . . . . 10-91
Jump Starting
Jump Starting . . . . . . . . . . . . . . 10-92
Towing
Towing the Vehicle . . . . . . . . . 10-97
Recreational Vehicle Towing . . . . . . . . . . . . . . . . . . . . 10-97
Appearance Care
Exterior Care . . . . . . . . . . . . . . 10-102
Interior Care . . . . . . . . . . . . . . . 10-105
Floor Mats . . . . . . . . . . . . . . . . 10-108
General Information
For service and parts needs,
visit your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:

Black plate (55,1)Chevrolet Silverado Owner Manual - 2012
Vehicle Care 10-55
20‐Inch Tires
If the vehicle has 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 9‑6 andAdding a Snow
Plow or Similar Equipment on
page 9‑115 for additional
information.
Notice: Low‐profile tires 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 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 examples show a typical
passenger and light truck 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.

Black plate (58,1)Chevrolet Silverado Owner Manual - 2012
10-58 Vehicle Care
(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 carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
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 mean
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.

Black plate (64,1)Chevrolet Silverado Owner Manual - 2012
10-64 Vehicle Care
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your tires and
transmit tire pressure readings to a
receiver located in the vehicle.
Each tire, including the spare
(if provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your
vehicle has been equipped with a
tire pressure monitoring system(TPMS) that illuminates a low tire
pressure telltale when one or
more of your tires is significantly
under‐inflated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inflate them
to the proper pressure. Driving on a
significantly under‐inflated tire
causes the tire to overheat and can
lead to tire failure. Under‐inflation
also reduces fuel efficiency and tire
tread life, and may affect the
vehicle's handling and stopping
ability.
Please note that the TPMS is
not a substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if under‐inflation has
not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been
equipped with a TPMS malfunction
indicator to indicate when the
system is not operating properly.
The TPMS malfunction indicator is
combined with the low tire pressure
telltale. When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start‐ups as
long as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.

Black plate (66,1)Chevrolet Silverado Owner Manual - 2012
10-66 Vehicle Care
A Tire and Loading Information label
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when
they are cold. SeeVehicle Load
Limits on page 9‑17, for an example
of the Tire and Loading Information
label and its location. Also see Tire
Pressure on page 10‑62.
The TPMS can warn about a
low tire pressure condition but it
does not replace normal tire
maintenance. See Tire Inspection
on page 10‑68, Tire Rotation on
page 10‑69 andTires on
page 10‑54.
Notice: Tire sealant materials are
not all the same. A non-approved
tire sealant could damage the
TPMS sensors. TPMS sensor
damage caused by using an
incorrect tire sealant is not
covered by the vehicle
warranty. Always use only the
GM-approved tire sealant
available through your dealer
or included in the vehicle.TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire pressure warning light
flashes for about one minute and
then stays on for the remainder of
the ignition cycle. A DIC warning
message also displays. The
malfunction light and DIC warning
message come on at each ignition
cycle until the problem is corrected.
Some of the conditions that can
cause these to come on are:
.One of the road tires has been
replaced with the spare tire.
The spare tire does not have a
TPMS sensor. The malfunction
light and the DIC message
should go off after the road tire
is replaced and the sensor
matching process is performed
successfully. See "TPMS Sensor
Matching Process" later in this
section.
.The TPMS sensor matching
process was not done or
not completed successfully
after rotating the tires.
The malfunction light and the
DIC message should go off after
successfully completing the
sensor matching process.
See "TPMS Sensor Matching
Process" later in this section.
.One or more TPMS sensors
are missing or damaged.
The malfunction light and the
DIC message should go off
when the TPMS sensors are
installed and the sensor
matching process is performed
successfully. See your dealer
for service.
.Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires on page 10‑72.

Black plate (68,1)Chevrolet Silverado Owner Manual - 2012
10-68 Vehicle Care
If the vehicle does not have RKE
or DIC buttons, press the trip
odometer reset stem located on
the instrument panel cluster until
the PRESS
VTO RELEARN
TIRE POSITIONS message
displays. The horn sounds twice
to signal the receiver is in
relearn mode and TIRE
LEARNING ACTIVE message
displays on the DIC screen.
4. Start with the driver side front tire.
5. Place the relearn tool against the tire sidewall, near the valve
stem. Then press the button to
activate the TPMS sensor.
A horn chirp confirms that the
sensor identification code has
been matched to this tire and
wheel position. 6. Proceed to the passenger side
front tire, and repeat the
procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat the
procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the procedure
in Step 5. The horn sounds
two times to indicate the sensor
identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire
and Loading Information label.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected
for signs of wear or damage at
least once a month.
Replace the tire if:
.The indicators at three or
more places around the tire
can be seen.
.There is cord or fabric
showing through the tire's
rubber.
.The tread or sidewall is
cracked, cut, or snagged
deep enough to show cord or
fabric.
.The tire has a bump, bulge,
or split.
.The tire has a puncture, cut,
or other damage that cannot
be repaired well because of
the size or location of the
damage.