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The low tire pressure warning light may come on in
cool weather when the vehicle is first started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inflated to the proper pressure.
A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s original
equipment tires and the correct inflation pressure for
your vehicle’s tires when they are cold. SeeLoading the
Vehicle on page 4-18, for an example of the Tire and
Loading Information label and its location on your vehicle.
Also seeInflation - Tire Pressure on page 5-62.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation
on page 5-69andTires on page 5-54.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.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 warning light
flashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until
the problem is corrected. Some of the conditions that
can cause the malfunction light and DIC message 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 TPMS malfunction light and DIC
message should go off once you re-install the
road tire containing the TPMS sensor.
•The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in this
section.
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When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
One way to tell when it
is time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining.
Some commercial truck tires, including
Goodyear LT225/75R16 G949 RSA and
Goodyear LT225/75R16 G933 RSD, may
not have treadwear indicators. If the tires do
not have treadwear indicators, replace the tires
when the tread depth is down to 1/8 inch (3.2 mm)
for the front tires, or 1/16 inch (1.6 mm) for the
rear tires.You need new tires if any of the following statements
are true:•You can see the indicators at three or more places
around the tire.
•You can see 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.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and inflation pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal injury
and vehicle damage, be sure to fit the jack lift
head into the proper location before raising the
vehicle.5. Raise the vehicle by turning the wheel wrench
clockwise. Raise the vehicle far enough off the
ground so there is enough room for the spare
tire to fit.
6. Remove all the
wheel nuts.
7. Take flat tire off of the mounting surface.
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6. Make sure the tire is stored securely. Push, pull (A),
and then try to turn (B) the tire. If the tire moves,
use the wheel wrench to tighten the cable.
You will hear two clicks when the tire is up all
the way.
7. Return the jacking equipment to the proper location.
Secure the items and replace the jack cover.
Spare Tire
This vehicle, when new, may have had a fully-inflated
spare tire. A spare tire may lose air over time, so check its
inflation pressure regularly. SeeInflation - Tire Pressure
on page 5-62andLoading the Vehicle on page 4-18for
information regarding proper tire inflation and loading the
vehicle. For instruction on how to remove, install or store
a spare tire, seeRemoving the Flat Tire and Installing the
Spare Tire on page 5-84andStoring a Flat or Spare Tire
and Tools on page 5-94.
After installing the spare tire on the vehicle, you should
stop as soon as possible and make sure the spare is
correctly inflated. The spare tire is made to perform well
at speeds up to 70 mph (112 km/h) at the recommended
inflation pressure, so you can finish your trip.
Have the damaged or flat road tire repaired or replaced
as soon as you can and installed back onto the vehicle.
This way, a spare tire will be available in case you need
it again. Do not mix tires and wheels of different sizes,
because they will not fit. Keep the spare tire and its
wheel together.
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Calling for Assistance
When calling Roadside Assistance, have the following
information ready:
•Your name, home address, and home telephone
number
•Telephone number of your location
•Location of the vehicle
•Model, year, color, and license plate number of the
vehicle
•Odometer reading, Vehicle Identification
Number (VIN), and delivery date of the vehicle
•Description of the problem
Coverage
Services are provided up to 5 years/100,000 miles
(160 000 km), whichever comes first.
In the U.S., anyone driving the vehicle is covered.
In Canada, a person driving the vehicle without
permission from the owner is not covered.
Roadside Assistance is not a part of the New Vehicle
Limited Warranty. GMC and General Motors of Canada
Limited reserve the right to make any changes or
discontinue the Roadside Assistance program at any
time without notification.GMC and General Motors of Canada Limited reserve the
right to limit services or payment to an owner or driver if
they decide the claims are made too often, or the same
type of claim is made many times.
Services Provided
•Emergency Fuel Delivery:Delivery of enough fuel
for the vehicle to get to the nearest service station.
•Lock-Out Service:Service is provided to unlock the
vehicle if you are locked out. A remote unlock may be
available if you have OnStar
®. For security reasons,
the driver must present identification before this
service is given.
•Emergency Tow From a Public Road or Highway:
Tow to the nearest GMC dealer for warranty service,
or if the vehicle was in a crash and cannot be driven.
Assistance is also given when the vehicle is stuck in
the sand, mud, or snow.
•Flat Tire Change:Service is provided to change a
flat tire with the spare tire. The spare tire, if equipped,
must be in good condition and properly inflated.
It is the owner’s responsibility for the repair or
replacement of the tire if it is not covered by the
warranty.
•Battery Jump Start:Service is provided to jump
start a dead battery.
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