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FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with either a
manually shifted transfer case or an electronically shifted
transfer case. Refer to the operating instructions for your
transfer case, located in this section for further informa-
tion.
Manually Shifted Transfer Case — If Equipped
The transfer case provides four mode positions.
•Two-wheel drive high range (2H)
•Four-wheel drive high range (4H)
•Neutral (N)
•Four-wheel drive low range (4L)
This transfer case is intended to be driven in the 2H
position for normal street and highway conditions such
as dry, hard surfaced roads.
When additional traction is required, the 4H and 4L
positions can be used to lock the front and rear drive-
shafts together and force the front and rear wheels to
rotate at the same speed. This is accomplished by simply
moving the shift lever to the desired positions once the
appropriate speed and gear requirements are met refer to
“Shifting Procedure – Manually Shifted Transfer Case” in
this section for further information. The 4H and 4L
positions are intended for loose, slippery road surfaces
only. Driving in the 4H and 4L positions on dry, hard
surfaced roads may cause increased tire wear and dam-
age to the driveline components.
The “Transfer Case Position Indicator Light” in the
instrument cluster will alert the driver that the vehicle is
in four-wheel drive and that the front and rear drive-
shafts are locked together. This light will illuminate when
the transfer case is shifted into either the 4H or 4L
position. There is no light for the 2H or NEUTRAL
positions on some models.
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•Entry/Exit Mode – Indicator lamp 3 will be illumi-
nated when the vehicle is in Entry Exit Mode. Entry/
Exit mode can be requested up to 33 mph (53 km/h).
If vehicle speed is reduced to, and kept below, 15 mph
(24 km/h) indicator lamp 4 will flash and indicator
lamp 3 will remain solid until Entry/Exit Mode is
achieved at which point indicator lamp 4 will turn off.
•Transport Mode – No indicator lamps will be illumi-
nated. Transport Mode is disabled by driving the
vehicle.
•Tire/Jack Mode – Indicator lamps 3 and 6 will be
illuminated. Tire/Jack Mode is disabled by driving the
vehicle.
•Wheel Alignment Mode – Indicator lamps 3 and 4 will
be illuminated. Wheel Alignment Mode is disabled by
driving the vehicle.
AIR SUSPENSION SYSTEM (2500/3500 MODELS) —
IF EQUIPPED
Description
The air suspension system is a rear leveling ride height
system. The main purpose of this system is to maintain
the truck’s rear ride height level.
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WARNING!(Continued)
attempt to drive the vehicle over 18 mph (29 km/h).
Driving faster than 18 mph (29 km/h) may cause loss
of control of the vehicle, which could result in
serious injury or death. Contact your local service
center for assistance.
SAFE OFF-ROAD DRIVING — POWER WAGON
ONLY
Off-Road Driving Tips And Vehicle Characteristics
Your vehicle has excellent on and off-road capabilities.
These off-road capabilities will allow you to explore
those wilderness trails where few travel, providing a
source of exciting and satisfying recreation. Before you
venture out, you should contact your local governmental
agency to determine the designated off-road vehicle
(ORV) trails or recreation areas. You should always tread
lightly and only use established roads, trails or ORV
recreational areas. The National Forest Service, Bureau of
Land Management or local Department of Natural Re-
sources are a wealth of information and usually have
maps with marked trails.
Skid Plates And Underbody Protection
Steel skid plates protect the major driveline components
of the truck including the fuel tank, transfer case and
steering damper. In addition, this vehicle is equipped
with boxed cross members and fore/aft rails. This addi-
tional protection allows the vehicle to be utilized in
severe off-road situations that would be considered im-
passable by a normal truck.
Ramp Travel Index (RTI)
The ramp travel index is the distance, in inches, that you
can drive your vehicle with one wheel on a 20-degree
ramp without lifting any other wheel off the ground. This
distance up the ramp divided by the wheelbase of the
vehicle and multiplied by 1,000 is the RTI. This vehicle
5
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TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P (Passenger) — Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
•European — Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letter#P#is absent from this tire
size designation. Example: 215/65R15 96H.
•LT (Light Truck) — Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
1—U.S.DOTSafetyStandardsCode (TIN)4—MaximumLoad
2—SizeDesignation 5—MaximumPressure3 — Service Description 6 — Treadwear, Traction andTemperature Grades
5
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•Temporary spare tires are designed for temporary
emergency use only. Temporary high pressure com-
pact spare tires have the letter “T” or “S” molded into
the sidewall preceding the size designation. Example:
T145/80D18 103M.
•High flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
Tire Sizing Chart
EXAMPLE:
Example Size Designation: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M, 31x10.5 R15 LT
P= Passenger car tire size based on U.S. design standards, or
%....blank....%= Passenger car tire based on European design standards, or
LT= Light truck tire based on U.S. design standards, or
TorS= Temporary spare tire or
31= Overall diameter in inches (in)
215, 235, 145= Section width in millimeters (mm)
65, 85, 80= Aspect ratio in percent (%)
– Ratio of section height to section width of tire, or
10.5= Section width in inches (in)
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CAUTION!(Continued)
•When replacing a flat, the spare tire may have to be
remounted on the rim, or installed at a different
location, to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the truck. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires and the white writing of the OWL tires will
maintain proper position.
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 (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 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 a
three 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.
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Vehicles With Full Size Spare
1. The matching full size spare wheel and tire assembly
has a TPM sensor that can be monitored 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, upon the next ignition switch cycle, a chime will
sound and the “Tire Pressure Monitoring Telltale
Light” will turn ON. In addition, the EVIC/DID will
display a “LOW TIRE” message and a graphic show-
ing the low tire pressure value in a different color. An
#Inflate to XX#message will also be displayed.
3. After driving the vehicle for up to 20 minutes above
15 mph (25 km/h) the “Tire Pressure Monitoring
Telltale Light” will turn OFF and the pressure value
will be updated and return to it’s original color, as
long as no tire pressure is below the low-pressure
warning limit in any of the four active road tires.
Tire Pressure Information System (TPIS) 3500
Series Trucks
Your vehicle may be equipped with a Tire Pressure
Information System (TPIS).
The Tire Pressure Information System (TPIS) uses wire-
less technology with wheel rim mounted electronic sen-
sors to transmit 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 check the
tire pressure in all of the tires on your vehicle monthly
and to maintain the proper pressure.
The TPIS consists of the following components:
•Receiver module
•Four TPM sensors (Single Rear Wheel (SRW) applica-
tions)
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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 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.
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