CAUTION!
Proper operation of four-wheel drive vehicles de-
pends on tires of equal size, type and circumference
on each wheel. Any difference in tire size can cause
damage to the transfer case. Tire rotation schedule
should be followed to balance tire wear.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitor System (TPMS) will warn the
driver of a low tire pressure based on the vehicle recom-
mended cold placard pressure.
The tire pressure will vary with temperature by about
1 psi (6.9 kPa) for every 12°F (6.5°C). This means that
when the outside temperature decreases, the tire pressure
will decrease. Tire pressure should always be set based
on cold inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km) after athree hour period. The cold tire inflation pressure must
not exceed the maximum inflation pressure molded into
the tire sidewall. Refer to “Tires – General Information”
in “Starting and Operating” for information on how to
properly inflate the vehicle’s tires. The tire pressure will
also increase as the vehicle is driven. This is normal and
there should be no adjustment for this increased pres-
sure.
The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low-pressure warning
limit for any reason, including low temperature effects
and natural pressure loss through the tire.
The TPMS will continue to warn the driver of low tire
pressure as long as the condition exists, and will not turn
off until the tire pressure is at or above the recommended
cold placard pressure. Once the low tire pressure warn-
ing (Tire Pressure Monitoring Telltale Light) illuminates,
you must increase the tire pressure to the recommended5
STARTING AND OPERATING 389
cold placard pressure in order for the “Tire Pressure
Monitoring Telltale Light” to turn off. The system will
automatically update and the “Tire Pressure Monitoring
Telltale Light” will turn off once the system receives the
updated tire pressures. 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.
For example, your vehicle may have a recommended
cold (parked for more than three hours) placard pressure
of 33 psi (227 kPa). If the ambient temperature is 68°F
(20°C) and the measured tire pressure is 28 psi (193 kPa),
a temperature drop to 20°F (-7°C) will decrease the tire
pressure to approximately 24 psi (165 kPa). This tire
pressure is low enough to turn ON the “Tire Pressure
Monitoring Telltale Light.” Driving the vehicle may cause
the tire pressure to rise to approximately 28 psi (193 kPa),
but the “Tire Pressure Monitoring Telltale Light” will still
be on. In this situation, the “Tire Pressure MonitoringTelltale Light” will turn off only after the tires are inflated
to the vehicle’s recommended cold placard pressure
value.
CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system
operation or sensor damage may result when us-
ing replacement equipment that is not of the same
size, type, and/or style. Aftermarket wheels can
cause sensor damage. Do not use aftermarket tire
sealants or balance beads if your vehicle is
equipped with a TPMS, as damage to the sensors
may result.
(Continued)
390 STARTING AND OPERATING
The TPMS consists of the following components:
•Receiver Module
•Four Tire Pressure Monitoring Sensors
•Tire Pressure Monitoring Telltale Light
The matching full-size spare wheel and tire assembly (if
equipped) has a tire pressure monitoring sensor. The
matching full-size spare can be used in place of any of the
four road tires. The TPMS will only monitor the pressure
in the full-size spare when it is used in place of a road
tire. Otherwise, a spare with a pressure below the low-
pressure limit will not cause the “Tire Pressure Monitor-
ing Telltale Light” to illuminate or the chime to sound.
Tire Pressure Monitoring Low Pressure Warnings
The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster, a “LOW TIRE
PRESSURE” message will display in the instru-
ment cluster, and a chime will sound when tire pressure
is low in one or more of the four active road tires. Should
this occur, you should stop as soon as possible, check the
inflation pressure of each tire on your vehicle, and inflate
each tire to the vehicle’s recommended cold placard
pressure value. Once the system receives the updated tire
pressures, the system will automatically update and the
“Tire Pressure Monitoring Telltale Light” will turn off.
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.
392 STARTING AND OPERATING
Service TPMS Warning
When a system fault is detected, the “Tire Pressure
Monitoring Telltale Light” will flash on and off for
75 seconds and then remain on solid. The system fault
will also sound a chime. If the ignition key is cycled, this
sequence will repeat, providing the system fault still
exists. The “Tire Pressure Monitoring Telltale Light” will
turn off when the fault condition no longer exists. 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.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” and
“LOW TIRE PRESSURE” message will turn on upon the
next ignition key cycle.
3. Driving the vehicle for up to 20 minutes above 15 mph
(24 km/h) will turn off the “TPMS Telltale Light,” as long
as no tire pressure is below the low-pressure warning
limit in any of the four active road tires.
Vehicles With Compact Spare
1. The compact spare tire does not have a tire pressure
monitoring sensor. Therefore, the TPMS will not monitor
the pressure in the compact spare tire.
5
STARTING AND OPERATING 393
•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 “LOW TIRE
PRESSURE” message for a minimum of five seconds and
a graphic showing the pressure values of each tire with
the low tire pressure values flashing.
5
STARTING AND OPERATING 395
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 the “SERVICE TPM
SYSTEM message 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.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 (24 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 PRES-
SURE” message to remind you to service the flat tire.
5
STARTING AND OPERATING 397
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options, trailer
tongue 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 or any given vehicle 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.
Tire Size
The tire size on the 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
5
STARTING AND OPERATING 407
Once A Month
•Check tire pressure and look for unusual wear or
damage.
•Inspect the battery and clean and tighten the terminals
as required.
•Check the fluid levels of the coolant reservoir and the
brake master cylinder, add as needed.
•Check all lights and other electrical items for correct
operation.
At Each Oil Change
•Change the engine oil filter.
•Inspect the brake hoses and lines.
CAUTION!
•Failure to perform the required maintenance items
may result in damage to the vehicle.
•Proper operation of four-wheel drive vehicles de-
pends on tires of equal size, type and circumfer-
ence on each wheel. Any difference in tire size can
cause damage to the transfer case. Tire rotation
schedule should be followed to balance tire wear.
Required Maintenance Intervals
Refer to the Maintenance Schedules on the following
pages for the required maintenance intervals.
8
M A I
N T
E
N A
N CE
S
C
H E
D
U L
E
S508 MAINTENANCE SCHEDULES