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WARNING!(Continued)
•Never use a tire with a smaller load index or
capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have a collision.
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body
clearance. Follow these recommendations to guard
against damage.
•Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer.
•Install on Rear Tires Only
•Due to limited clearance, RUD-GRIP 4X4 or Equivalent
is recommended on P295/45R20 tires.
WARNING!
Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
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TIRE PRESSURE MONITOR SYSTEM (TPMS)
NOTE:For vehicles equipped with run flat tires — When
the TPMS indicates a tire pressure of 14 psi (96 kPa) or
lower, always check tire pressure and replace the tire at
the first opportunity. At inflation pressure of/or below 14
psi (96 kPa) the tire is in the run-flat mode of operation.
In this condition, it is recommended a vehicle maximum
speed of 50 mph (80 km/h) for a maximum distance of 50
miles (80 km). The manufacturer does not recommend
using the run flat feature while driving a vehicle loaded
at full capacity or towing a trailer.
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold tire pressure.
The tire pressure will vary with temperature by about 1
psi (7 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 oncold 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 a
three-hour period.Refer to “Tires – General Informa-
tion” 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 pressure.
The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low pressure warning
threshold for any reason, including low temperature
effects, or 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 recommended
cold tire pressure. Once the low tire pressure warning has
been illuminated, the tire pressure must be increased to
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Page 481 of 636

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 andrear 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.
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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 weightvalues 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 heavier
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exceed the GVWR. Refer to “Vehicle Loading/Vehicle
Certification Label” in “Starting And Operating” for
further information.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the weight of all
cargo, consumables and equipment (permanent or tem-
porary) loaded in or on the trailer in itsloaded and
ready for operationcondition.
The recommended way to measure GTW is to put your
fully loaded trailer on a vehicle scale. The entire weight
of the trailer must be supported by the scale.
WARNING!
If the gross trailer weight is 5,000 lbs (2 267 kg) or
more, it is mandatory to use a weight-distributing
hitch to ensure stable handling of your vehicle. If
(Continued)
WARNING!(Continued)
you use a standard weight-carrying hitch, you could
lose control of your vehicle and cause a collision.
Gross Combination Weight Rating (GCWR)
The GCWR is the total permissible weight of your vehicle
and trailer when weighed in combination.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front and rear
axles. Distribute the load over the front and rear axles
evenly. Make sure that you do not exceed either front or
rear GAWR. Refer to “Vehicle Loading/Vehicle Certifica-
tion Label” in “Starting And Operating” for further
information.
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Trailer Towing Weights (Maximum Trailer Weight Ratings)
Engine/
TransmissionGCWR (Gross
Combined Wt. Rat-
ing)Frontal AreaMax. GTW (Gross
Trailer Wt.)Max. Trailer Tongue
Wt. (See Note)
6.4L Automatic
12,600 lbs (5 715 kg)55 sq ft (5.11 sq m) 7,200 lbs (3 265 kg) 720 lbs (327 kg)
Refer to local laws for maximum trailer towing speeds.
NOTE:
•The trailer tongue weight must be considered as part
of the combined weight of occupants and cargo, and
should never exceed the weight referenced on the Tire
and Loading Information placard. Refer to “Tire–
Safety Information” in “Starting and Operating” for
further information.•The manufacturer does not recommend using the run
flat feature while driving a vehicle loaded at full
capacity or towing a trailer.
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Towing Requirements — Trailer Brakes
WARNING!
•Do not connect trailer brakes to your vehicle’s
hydraulic brake lines. It can overload your brake
system and cause it to fail. You might not have
brakes when you need them and could have an
accident.
•Towing any trailer will increase your stopping
distance. When towing you should allow for addi-
tional space between your vehicle and the vehicle
in front of you. Failure to do so could result in an
accident.
CAUTION!
If the trailer weighs more than 1,000 lbs (454 kg)
loaded, it should have its own brakes and they
should be of adequate capacity. Failure to do this
could lead to accelerated brake lining wear, higher
brake pedal effort, and longer stopping distances.
•Donotinterconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
•An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
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•Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
1,653 lbs (750 kg).
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 pres-
sures 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 tirereplacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Tips
NOTE:To provide optimum towing performance and to
protect transmission components always select TOW
mode when towing a trailer. Before setting out on a trip,
practice turning, stopping and backing the trailer in an
area away from heavy traffic.
Automatic Transmission
The DRIVE range can be selected when towing. The
transmission controls include a drive strategy to avoid
frequent shifting when towing. However, if frequent
shifting does occur while in DRIVE, select TOW mode, or
use the Paddle Shift switches to manually select a lower
gear.
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