2009 DODGE RAM 3500 DIESEL differential

▫Electronically Shifted Transfer Case
Operating Information/Precautions (Four
Position Switch) — If Equipped .......... 272
▫ Shifting Procedure — Electronically Shifted
Transfer Case ....................... 276
 Axle Locker System — Power Wagon Only . . 279
 Stabilizer/Sway Bar System — Power Wagon
Only ............................... 282
 Safe Off-Road Driving — Power Wagon
Only ............................... 284
▫ Off-Road Driving Tips And Vehicle
Characteristics ...................... 284
▫ Driving In Snow, Mud And Sand ........ 289
▫ Crossing Obstacles (Rocks And Other High
Points) ............................ 290
▫ Hill Climbing ...................... 293 ▫
Driving Through Water ............... 295
▫ Airing Down For Off-Road Driving ...... 298
▫ Vehicle Recovery ................... 299
▫ After Driving Off-Road ............... 302
 Limited-Slip Differential – If Equipped ..... 304
 Driving On Slippery Surfaces ............ 304
 Driving Through Water ................ 305
▫ Flowing/Rising Water ................ 305
▫ Shallow Standing Water .............. 305
 Driving Off-Road — Ram Truck Only ...... 307
 Winch Usage – If Equipped (Power Wagon
Only) ............................... 308
▫ Things To Know Before Using Your
Winch ............................ 308
248 STARTING AND OPERATING

AXLE LOCKER SYSTEM — POWER WAGON
ONLYThis vehicle 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 prevents it from becoming
stuck. The locking front and rear differentials should only
be engaged during low-speed, extreme off-road situa-
tions where one wheel is likely to not be in contact with
the ground. It is not recommended to drive the vehicle
with the differentials locked on pavement due to the
reduced ability to turn and speed limitations.
CAUTION!
•
Do not lock the front or rear axle on hard surfaced
roads. The ability to steer the vehicle is reduced
and damage to the drivetrain may occur when the
axles are locked on hard surfaced roads.
•
Do not try to lock the rear axle if the vehicle is
stuck and the tires are spinning. You can damage
drivetrain components. Lock the rear axle before
attempting situations or navigating terrain, which
could possibly cause the vehicle to become stuck.
STARTING AND OPERATING 279
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The locking axles are controlled by the axle locker switch
located on the center console.
The switch has three positions, AXLE UNLOCK, REAR
LOCK, and FRONT/REAR LOCK. Under normal driv-
ing conditions, the switch should be left in the AXLE
UNLOCK position. In the AXLE UNLOCK position, thefront and rear axles are unlocked. In the REAR LOCK
position, the rear axle is locked. In the FRONT/REAR
LOCK position, the front and rear axles are locked.
NOTE:
Even when the axles are in the AXLE UNLOCK
position, the limited slip differential in the rear axle still
provides torque biasing capability for moderate low
traction environments.
During the command to lock the axle, the indicator light
will flash until the axle is locked. After the lock command
has been successfully executed, the light will remain on
solid.
To lock the rear axle, place the vehicle in 4LO. Refer to
“Four Wheel Drive Operation” in this section of the
manual. Move the axle locker switch position to REAR
LOCK while traveling less than 3 mph (5 km/h). The RR
indicator light will remain on when the rear axle is
locked.
Locking Axle Switch
280 STARTING AND OPERATING

Water Fording CharacteristicsWater fording characteristic is the vehicle’s ability to
cross a body of still water, where the powertrain and
drivetrain are safe from water ingestion. This vehicle has
high water fording characteristics with the ability to cross
a pool of water, without stopping, 24 inches deep at a
maximum speed of 10 mph (16 km/h) and a pool of
water 30 inches deep at a maximum speed of 5 mph
(8 km/h), both with an entrance ramp angle of 1.3
degrees.
CAUTION!
The door sill height is 25 inches. Water may intrude
into the interior of the vehicle at greater depths.Simultaneous Brake And Throttle OperationMany off-road driving conditions require the simulta-
neous use of the brake and throttle (two footed driving).
When climbing rocks, logs, or other stepped objects,
Front and Rear (Shown) Differential Height E
STARTING AND OPERATING 287
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your vehicle’s abilities and be able to recover it if
something goes wrong. You should never stop or shut a
vehicle off when crossing deep water unless you ingested
water into the engine air intake. If the engine stalls do not
attempt to restart it. Determine if it has ingested water
first. The key to any crossing is low and slow. You want
to use 1st gear in 4L (Low Range) and proceed very
slowly with a constant slow speed (3-5 mph [5–8 km/h]
maximum) and light throttle. Keep the vehicle moving;
do not try to accelerate through the crossing. After
crossing any water higher than the bottom of the axle
differentials, you should inspect all of the vehicle fluids
for signs of water ingestion.
CAUTION!
Water ingestion into the axles, transmission, transfer
case, engine or vehicle interior can occur if you drive
too fast or through too deep of water. Water can cause
permanent damage to engine, driveline or other
vehicle components and your brakes will be less
effective once wet and/or muddy•
Before You Cross Any Type Of Water– As you
approach any type of water you need to determine if
you can cross it safely and responsibly. If necessary, get
out and walk through the water or probe it with a
stick. You need to be sure of its depth, approach angle,
current and bottom condition. Be careful of murky or
muddy waters, check for hidden obstacles. Make sure
you will not be intruding on any wildlife and you can
recover the vehicle if necessary. The key to a safe
296 STARTING AND OPERATING

LIMITED-SLIP DIFFERENTIAL – IF EQUIPPEDThe limited-slip differential provides additional traction
on snow, ice, mud, sand and gravel, particularly when
there is a difference between the traction characteristics
of the surface under the right and left rear wheels. During
normal driving and cornering, the limited-slip unit per-
forms similarly to a conventional differential. On slip-
pery surfaces, however, the differential delivers more of
the driving effort to the rear wheel having the better
traction.
The limited-slip differential is especially helpful during
slippery driving conditions. With both rear wheels on a
slippery surface, a slight application of the accelerator
will supply maximum traction. When starting with only
one rear wheel on an excessively slippery surface, slight
momentary application of the parking brake may be
necessary to gain maximum traction.
WARNING!
On vehicles equipped with a limited-slip differential
never run the engine with one rear wheel off the
ground since the vehicle may drive through the rear
wheel remaining on the ground. You could lose
control of the vehicle.
Care should be taken to avoid sudden accelerations when
both rear wheels are on a slippery surface. This could
cause both rear wheels to spin, and allow the vehicle to
slide sideways on the crowned surface of a road or in a
turn.DRIVING ON SLIPPERY SURFACESWhen driving on wet or slushy roads, it is possible for a
wedge of water to build up between the tire and road
surface. This is known as hydroplaning and may cause
partial or complete loss of vehicle control and stopping
304 STARTING AND OPERATING

NOTE:ABS improves steering control of the vehicle
during hard braking maneuvers.
WARNING!
•
ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that af-
forded by the condition of the vehicle brakes and
tires or the traction afforded.
•
The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•
The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
Traction Control System (TCS)The TCS monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s), and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS functions similar to a
limited-slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in the
“Partial Off” mode. Refer to “Electronic Stability Pro-
gram (ESP)” in this section of this manual. This brake
pressure modulation transfers drive torque from slipping
to non-slipping wheels to provide optimal forward
traction.
334 STARTING AND OPERATING

CAUTION!
Never use a floor jack directly under the differential
housing of a loaded truck or damage to your vehicle
may result.JUMP-STARTING PROCEDURESDo not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic transmis-
sion cannot be started this way. Also, there is a greater
risk of an accident when a vehicle is being pushed or
towed. If the vehicle has a discharged battery, booster
cables may be used to obtain a start from a booster
battery or the battery in another vehicle. This type of start
can be dangerous if done improperly, so follow this
procedure carefully.
WARNING!
•
Battery fluid is a corrosive acid solution; do not
allow battery fluid to contact eyes, skin or cloth-
ing. Don’t lean over battery when attaching
clamps or allow the clamps to touch each other. If
acid splashes in eyes or on skin, flush contami-
nated area immediately with large quantities of
water.
•
A battery generates hydrogen gas which is flam-
mable and explosive. Keep flame or spark away
from the vent holes.
•
Do not use a booster battery or any other booster
source that has a greater than 12-Volt system, i.e.,
do not use a 24-Volt power source.
1. Remove all metal jewelry such as watch bands or
bracelets which might make an unintended electrical
contact.
WHAT TO DO IN EMERGENCIES 419
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