
below the low-pressure warning limit in any of the
four active road tires. The vehicle may need to be
driven for up to 20 minutes above 15 mph (24 km/h)
in order for the TPMS to receive this information.
Premium System – If Equipped
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim-mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.
NOTE: It is particularly important, for you to regularly
check the tire pressure in all of your tires and to maintain
the proper pressure. The Tire Pressure Monitor System (TPMS) consists of the
following components:
• Receiver Module
• Four Tire Pressure Monitoring Sensors
• Various Tire Pressure Monitoring System Messages,
which display in the Electronic Vehicle Information
Center (EVIC), and a graphic displaying tire pressures
• Tire Pressure Monitoring Telltale Light
A tire pressure monitoring sensor is located in the spare
wheel, if the vehicle is equipped with a matching full-size
spare wheel and tire assembly. The matching full-size
spare tire can be used in place of any of the four road
tires.
5 STARTING AND OPERATING 501

If the ignition switch is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the “Tire Pressure Monitoring Telltale
Light” will no longer flash, the SERVICE TPM SYSTEM
message will not be present, and a pressure value will be
displayed instead of dashes. A system fault can occur by
any of the following:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the
TPM sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.
3. Lots of snow or ice around the wheels or wheel
housings.
4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors. The EVIC will also display a SERVICE TPM SYSTEM
message for a minimum of five seconds when a system
fault is detected possibly related to an incorrect sensor
location fault. In this case, the SERVICE TPM SYSTEM
message is then followed by a graphic display, with
pressure values still shown. This indicates the pressure
values are still being received from the TPM Sensors but
they may not be located in the correct vehicle position.
However, the system still needs to be serviced as long as
the SERVICE TPM SYSTEM message exists.
NOTE:
•
If your vehicle is equipped with a matching full-size
spare wheel and tire assembly, it has a tire pressure
monitoring sensor, and can be monitored by the Tire
Pressure Monitoring System (TPMS). In the event that
the matching full-size spare tire is swapped with a low
pressure road tire, the next ignition switch cycle will still
show the “Tire Pressure Monitoring Telltale Light” to be
ON, a chime to sound, a “LOW TIRE PRESSURE”504 STARTING AND OPERATING

message to appear in the EVIC, and the graphic display
will still show the low tire pressure value “flashing.”
Driving the vehicle for up to 20 minutes above 15 mph
(24 km/h) will turn OFF the “Tire Pressure Monitoring
Telltale Light” as long as none of road tires are below the
low pressure warning threshold.
• If your vehicle is not equipped with a matching
full-size spare wheel and tire assembly, it does not
have a tire pressure monitoring sensor in the spare tire.
The TPMS will not be able to monitor the tire pressure.
If you install the spare tire in place of a road tire that
has a pressure below the low-pressure warning limit,
upon the next ignition switch cycle, the “Tire Pressure
Monitoring Telltale Light” will remain ON, a chime
will sound, and the EVIC will still display a “flashing”
pressure value in the graphic display. After driving the
vehicle for up to 20 minutes above 15 mph (24 km/h),
the “Tire Pressure Monitoring Telltale Light” will flash
on and off for 75 seconds and then remain on solid. In addition, the EVIC will display a “SERVICE TPM
SYSTEM message for a minimum of five seconds and
then display dashes (- -) in place of the pressure value.
For each subsequent ignition switch cycle, a chime will
sound, the “Tire Pressure Monitoring Telltale Light”
will flash on and off for 75 seconds and then remain on
solid, and the EVIC will display a SERVICE TPM
SYSTEM message for a minimum of five seconds and
then display dashes (- -) in place of the pressure value.
Once you repair or replace the original road tire, and
reinstall it on the vehicle in place of the spare tire, the
TPMS will update automatically.
In addition, the “Tire Pressure Monitoring Telltale Light”
will turn OFF and the graphic in the EVIC will display a
new pressure value instead of dashes (- -), as long as no
tire pressure is below the low-pressure warning limit in
any of the four active road tires. The vehicle may need to
be driven for up to 20 minutes above 15 mph (24 km/h)
in order for the TPMS to receive this information. 5 STARTING AND OPERATING 505

VEHICLE LOADING
Certification Label
As required by National Highway Traffic Safety Admin-
istration regulations, your vehicle has a certification label
affixed to the driver’s side door or pillar.
This label contains the month and year of manufacture,
Gross Vehicle Weight Rating (GVWR), Gross Axle Weight
Rating (GAWR) front and rear, and Vehicle Identification
Number (VIN). A Month-Day-Hour (MDH) number is
included on this label and indicates the Month, Day and
Hour of manufacture. The bar code that appears on the
bottom of the label is your VIN.
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
5 STARTING AND OPERATING 513

Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires
must be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commer-
cial scale to insure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should
then be determined separately to be sure that the load is
properly distributed over the front and rear axle. Weigh-
ing the vehicle may show that the GAWR of either the
front or rear axles has been exceeded but the total load is
within the specified GVWR. If so, weight must be shifted
from front to rear or rear to front as appropriate until the
specified weight limitations are met. Store the heavier514 STARTING AND OPERATING

WARNING!Improper towing can lead to a collision. Follow these
guidelines to make your trailer towing as safe as
possible:
• Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have a collision.
• When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age to the brakes, axle, engine, transmission, steer-
ing, suspension, chassis structure or tires. (Continued) WARNING! (Continued)• Safety chains must always be used between your
vehicle and trailer. Always connect the chains to
the frame or hook retainers of the vehicle hitch.
Cross the chains under the trailer tongue and allow
enough slack for turning corners.
• Vehicles with trailers should not be parked on a
grade. When parking, apply the parking brake on
the tow vehicle. Put the tow vehicle automatic
transmission in PARK. With a manual transmis-
sion, shift the transmission into first gear. And
with four-wheel-drive vehicles, make sure the
transfer case is not in N (Neutral). Always, block or
chock the trailer wheels.
• GCWR must not be exceeded. (Continued)526 STARTING AND OPERATING

WARNING! (Continued)• Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
4. Tongue weight rating for the trailer hitch utilized
(This requirement may limit the ability to always
achieve the 10% to 15% range of tongue weight as
a percentage of total trailer weight). Towing Requirements – Tires
– Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
– Check the trailer tires for proper tire inflation pressures
before trailer usage.
– Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for proper
inspection procedure.
– When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for proper tire
replacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
5 STARTING AND OPERATING 527

JACKING AND TIRE CHANGING
WARNING!• Do not attempt to change a tire on the side of the
vehicle close to moving traffic. Pull far enough off
the road to avoid the danger of being hit when
operating the jack or changing the wheel.
• Being under a jacked-up vehicle is dangerous. The
vehicle could slip off the jack and fall on you. You
could be crushed. Never put any part of your body
under a vehicle that is on a jack. If you need to get
under a raised vehicle, take it to a service center
where it can be raised on a lift. (Continued) WARNING! (Continued)• Never start or run the engine while the vehicle is
on a jack.
• The jack is designed to be used as a tool for
changing tires only. The jack should not be used to
lift the vehicle for service purposes. The vehicle
should be jacked on a firm level surface only.
Avoid ice or slippery areas.540 WHAT TO DO IN EMERGENCIES