
vehicle’s mobility. Approach these obstacles at a 45-
degree angle and let each tire go through the obstacle
independently. You need to use caution when crossing
large obstacles with steep sides. Do not attempt to cross
any large obstacle with steep sides at an angle great
enough to put the vehicle at risk of a rollover. If you get
caught in a rut, dig a small trench to the right or left at a
45-degree angle ahead of the front tires. Use the removed
dirt to fill the rut ahead of the turnout you just created.
You should now be able to drive out following the trench
you just created at a 45-degree angle.
WARNING!
There is an increased risk of rollover when crossing
an obstacle, at any angle, with steep sides.
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake and
accelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.
CAUTION!
Do not attempt to cross a log with a greater diameter
than the running ground clearance or the vehicle will
become high centered.
Getting High Centered
If you get hung up or high centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody and
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STARTING AND OPERATING 575

apply more power as you start up the hill. Do not race
forward into a steep grade, the abrupt change of grade
could cause you to lose control. If the front end begins
to bounce, ease off the throttle slightly to bring all four
tires back on the ground. As you approach the crest of
the hill ease off the throttle and slowly proceed over
the top. If the wheels start to slip as you approach the
crest of a hill, ease off the accelerator and maintain
headway by turning the steering wheel no more than
a ¼ turn quickly back and forth. This will provide a
freshbiteinto the surface and will usually provide
enough traction to complete the climb. If you do not
make it to the top, place the vehicle in REVERSE and
back straight down the grade using engine resistance
along with the vehicle brakes.WARNING!
Never attempt to climb a hill at an angle or turn
around on a steep grade. Driving across an incline
increases the risk of a roll over, which may result in
severe injury or death.
•Driving Down Hill– Before driving down a steep hill
you need to determine if it is too steep for a safe
descent. What is the surface traction? Is the grade too
steep to maintain a slow controlled descent? Are there
obstacles? Is it a straight descent? Is there plenty of
distance at the base of the hill to regain control if the
vehicle descends too fast? If you feel confident in your
ability to proceed then make sure you are in 4L (Low
Range) with the transmission in first gear (manually
select first gear on automatic transmissions) and pro-
ceed with caution. Allow engine braking to control the
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WARNING!(Continued)
•Be sure the parking brake is fully disengaged
before driving; failure to do so can lead to brake
failure and a collision.
•Always fully apply the parking brake when leav-
ing your vehicle or it may roll and cause damage or
injury. Also, be certain to leave the transmission in
PARK. Failure to do so may cause the vehicle to roll
and cause damage or injury.
CAUTION!
If the Brake System Warning Light remains on with
the parking brake released, a brake system malfunc-
tion is indicated. Have the brake system serviced by
an authorized dealer immediately.
BRAKE SYSTEM
If power assist is lost for any reason (for example,
repeated brake applications with the engine off), the
brakes will still function. However, you will experience a
substantial increase in braking effort to stop the vehicle.
If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still func-
tion with some loss of overall braking effectiveness. This
will be evident by increased pedal travel during applica-
tion, greater pedal force required to slow or stop, and
activation of the “Brake Warning Light” and the “ABS
Warning Light” (if equipped) during brake use.
Hydraulic Brake Assist — 2500/3500 Models Only
(Except Power Wagon)
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steering
618 STARTING AND OPERATING

items down low and be sure that the weight is distributed
equally. Stow all loose items securely before driving.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
CAUTION!
Do not load your vehicle any heavier than the GVWR
or the maximum front and rear GAWR. If you do,
parts on your vehicle can break, or it can change the
way your vehicle handles. This could cause you to
lose control. Also overloading can shorten the life of
your vehicle.
TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer, carefully
review this information to tow your load as efficiently
and safely as possible.
To maintain the New Vehicle Limited Warranty coverage,
follow the requirements and recommendations in this
manual concerning vehicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
688 STARTING AND OPERATING

WARNING!
It is important that you do not exceed the maximum
front or rear GAWR. A dangerous driving condition
can result if either rating is exceeded. You could lose
control of the vehicle and have an accident.
Tongue Weight (TW)
The tongue weight is the downward force exerted on the
hitch ball by the trailer. The recommended tongue weight
is 10% to 15% of the vehicle’s GTW for a conventional
hitch. You must consider this as part of the load on your
vehicle.
Frontal Area
The frontal area is the maximum height multiplied by the
maximum width of the front of a trailer.
Trailer Sway Control
The trailer sway control can be a mechanical telescoping
link that can be installed between the hitch receiver and
the trailer tongue that typically provides adjustable fric-
tion associated with the telescoping motion to dampen
any unwanted trailer swaying motions while traveling.
If equipped, the electronic Trailer Sway Control (TSC)
recognizes a swaying trailer and automatically applies
individual wheel brakes and/or reduces engine power to
attempt to eliminate the trailer sway.
Weight-Carrying Hitch
A weight-carrying hitch supports the trailer tongue
weight, just as if it were luggage located at a hitch ball or
some other connecting point of the vehicle. These kinds
of hitches are the most popular on the market today and
they are commonly used to tow small and medium sized
trailers.
690 STARTING AND OPERATING

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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Cavity Cartridge Fuse Micro Fuse Description
F24 30 Amp Pink – Driver Door Module
F25 30 Amp Pink – Front Wiper
F26 30 Amp Pink – Antilock Brakes / Stability Control Module /
Valves
F28 20 Amp Blue – Trailer Tow Backup Lights – If Equipped
F29 20 Amp Blue – Trailer Tow Parking Lights – If Equipped
F30 30 Amp Pink – Trailer Tow Receptacle
F31 30 Amp Pink (1500
LD Diesel)– Urea Heater Control – If Equipped
F32 – – Spare Fuse
F33 20 Amp Blue – Special Services Vehicle Only
F34 30 Amp Pink – Vehicle System Interface Module #2 – If
Equipped
F35 30 Amp Pink – Sunroof – If Equipped
F36 30 Amp Pink – Rear Defroster – If Equipped
842 MAINTAINING YOUR VEHICLE

Cavity Cartridge Fuse Micro Fuse Description
F69 – 15 Amp Blue Mod SCR 12V (Cummins Diesel) – If Equipped
F70 – 30 Amp Green Fuel Pump Motor
F71 – 25 Amp Clear Amplifier
F72 – 10 Amp Red PCM – If Equipped
F73 – 20 Amp Yellow Fuel Transfer Pump (HD Only) – If Equipped
F74 – 20 Amp Yellow (Gas
Engine & 1500 LD
Diesel)Brake Vacuum Pump Gas/Diesel – If Equipped
F75 – 10 Amp Red Coolant Temperature Valve Actuator
F76 – 10 Amp Red Antilock Brakes / Electronic Stability Control
F77 – 10 Amp Red Drivetrain Control Module/Front Axle Discon-
nect Module
F78 – 10 Amp Red Engine Control Module / Electric Power Steer-
ing
F79 – 15 Amp Blue Clearance Lights
7
MAINTAINING YOUR VEHICLE 845