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POWER WAGON FEATURES
Locking Front and Rear Differentials
Most 4WD trucks are equipped with open differentials
front and rear. This design is used because it allows each
wheel to turn independently helping to eliminate bind-
ing when cornering. A disadvantage of using an open
differential is when one or more wheels lose traction; all
of the power is directed to those wheels resulting in a loss
of momentum. The Power Wagon is equipped with
electronically locking front and rear differentials. These
differentials, when engaged, mechanically lock together
the axle shafts forcing the wheels to spin at an equal rate.
This allows the vehicle to maintain its momentum and
thus prevents it from becoming stuck. The locking front
and rear differentials should only be engaged during
low-speed, extreme off-road situations where one wheel
is likely to not be in contact with the ground. It is notrecommended to drive the vehicle with the differentials
locked on pavement due to the reduced ability to turn
and speed limitations.
4.56:1 Gears
This is the highest axle ratio available in a full-size
pickup. The high gearing helps to compensate for the
increased rolling mass and increase diameter of the
off-road tires. As well, there are many advantages to a
higher axle ratio in off-road applications. When driving
downhill the high gearing enables the driver to use the
engine to slow the vehicle down in a more controlled
manner. When driving up a steep grade, the ratio helps
by keeping the truck in its power band helping to
maintain upward momentum.
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Proper operation of 4-wheel-drive vehicles depends on
tires of equal size, type and circumference on each wheel.
Any difference will adversely affect shifting and can
cause damage to the transfer case.
NOTE:Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
Because 4-wheel drive provides improved traction, there
is a tendency to exceed safe turning and stopping speeds.
Do not go faster than road conditions permit.
NOTE:Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the
Neutral (N) position without first fully engaging the
parking brake. The transfer case Neutral (N) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
For additional information on the appropriate use of each
transfer case mode position see the information below:
2H
Rear Wheel Drive High Range - Normal street and
highway driving. Dry hard surfaced roads.
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POWER STEERING
Your power steering system will provide mechanical
steering capability if power assist is lost.
If for any reason the hydraulic pressure is interrupted, it
will still be possible to steer your vehicle. Under these
conditions you will experience a substantial increase in
steering effort.
MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE:The MDS system may take some time to return
to full functionality after a battery disconnect.
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 designation. Ex-
ample: P215/65R15 95H.
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•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 letterPis 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.
•Temporary Spare tires are high pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
•High Flotation tire sizing is based on U.S. design
standards and begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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Tire Sizing Chart
EXAMPLE:
Size Designation:
P= Passenger car tire size based on U.S. design standards
....blank....= Passenger car tire based on European design standards
LT= Light Truck tire based on U.S. design standards
T= Temporary Spare tire
31= Overall Diameter in Inches (in)
215= Section Width in Milimeters (mm)
65= Aspect Ratio in Percent (%)
—Ratio of section height to section width of tire.
10.5= Section Width in Inches (in)
R= Construction Code
—Rmeans Radial Construction.
—Dmeans Diagonal or Bias Construction.
15= Rim Diameter in Inches (in)
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Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire
however the date code may only be on one side. Tires
with white sidewalls will have the full TIN including
date code located on the white sidewall side of the tire.Look for the TIN on the outboard side of black sidewall
tires as mounted on the vehicle. If the TIN is not found on
the outboard side then you will find it on the inboard side
of the tire.
EXAMPLE:
DOT MA L9 ABCD 0301
DOT= Department of Transportation
—This symbol certifies that the tire is in compliance with the U.S. Department of Transportation tire
safety standards, and is approved for highway use.
MA= Code representing the tire manufacturing location.(2 digits)
L9= Code representing the tire size.(2 digits)
ABCD= Code used by tire manufacturer.(1 to 4 digits)
03= Number representing the week in which the tire was manufactured.(2 digits)
—03 means the 3rd week.
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Tire and Loading Information Placard
This placard tells you important information about the:
1) number of people that can be carried in the vehicle
2) the total weight your vehicle can carry
3) the tire size designed for your vehicle
4) the cold tire inflation pressures for the front, rear
and spare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size and cold tire
inflation pressures specified on the Tire and Loading
Information placard and the Vehicle Loading section of
this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWR’s) for the front and rear
axles must not be exceeded. For further information on
GAWR’s, vehicle loading and trailer towing, see the
Vehicle Loading section of this manual.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX kg or XXX
lbs.” on the Tire and Loading Information placard. The
Tire and Loading Information
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Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have an accident result-
ing in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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