
•Three Trigger modules (mounted in three of the four
wheel-wells)
•Various Tire Pressure Monitoring System messages,
which display in the Electronic Vehicle Information
Center (EVIC)
•Tire Pressure Monitoring Telltale light
The matching full size spare wheel and tire assembly (if
equipped) has a tire pressure monitoring sensor. The full
size spare can be used in place of any of the four road
tires. A spare with a pressure below the low-pressure
limit will not cause the Tire Pressure Monitoring Telltale
light to illuminate or the chime to sound. However, it will
cause a “SPARE LOW PRESSURE” message to display in
the EVIC.
Tire Pressure Monitoring Low Pressure Warnings
The Tire Pressure Monitoring Telltale light will
illuminate in the instrument cluster and a chime
will sound when tire pressure is low in one or
more of the four active road tires. In addition, the
Electronic Vehicle Information Center (EVIC) will display
a graphic showing the pressure values of each tire with
the low tire pressure values flashing.
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If the ignition key 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, and theCHECK TPM SYS-
TEMmessage will no longer display, and a pressure
value will display in place of the dashes. A system fault
can occur due to any of the following:
1. Jamming due to electronic devices or driving next to
facilities emitting the same radio frequencies as the TPMS
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 TPMS sensors.NOTE:
Vehicles with Full-Size Spare
1. The matching full size spare wheel and tire assembly
has a tire pressure monitoring sensor that can be moni-
tored by the TPMS.
2. If you install the full size spare in place of a road tire
that has a pressure below the low-pressure warning limit,
a chime will sound and the TPMS Telltale light will turn
on upon the next ignition key cycle. In addition, the EVIC
will display a Low Pressure message and a graphic
showing the low tire pressure value flashing.
3. After driving the vehicle for up to 20 minutes above
15 mph (25 km/h) the TPMS Telltale light will turn OFF,
as long as no tire pressure is below the low-pressure
warning limit in any of the four active road tires.
4.
The EVIC will display a graphic showing the tire pressure
value in place of the flashing low tire pressure value. The
EVIC will also display a “SPARE LOW PRESSURE” message
to remind you to service the flat tire.
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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 B-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, trailertongue weight, and cargo. The label also specifies maxi-
mum 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’s 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 ve-
hicle’s GVWR.
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Trailer and Tongue Weight
Always load a trailer with 60% to 65% of the weight in
the front of the trailer. This places 10% to 15% of the
Gross Trailer Weight (GTW) on the tow hitch of your
vehicle. Loads balanced over the wheels or heavier in the
rear can cause the trailer to swayseverelyfrom side-to-
side which will cause loss of control of vehicle and trailer.
Failure to load trailers heavier in front is the cause of
many trailer accidents.
Never exceed the maximum tongue weight stamped on
your bumper or trailer hitch.
Consider the following items when computing the
weight on the rear axle of the vehicle:
•The tongue weight of the trailer.
•The weight of any other type of cargo or equipment
put in or on your vehicle.
•The weight of the driver and all passengers.
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WARNING! (Continued)
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 an accident.
•When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, chas-
sis structure or tires.
•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 transmission in PARK.
Always, block orchockthe trailer wheels.
•GCWR must not be exceeded.
•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).
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