2013 Ram 2500 differential

▫Off-Road Driving Tips And Vehicle
Characteristics ...................... .422
▫ Driving In Snow, Mud And Sand ..........425
▫ Crossing Obstacles (Rocks And Other High
Points) ............................ .427
▫ Hill Climbing ....................... .429
▫ Driving Through Water .................432
▫ Airing Down For Off-Road Driving .........435
▫ Vehicle Recovery ..................... .436
▫ After Driving Off-Road .................440
 LIMITED-SLIP DIFFERENTIAL .............441
 DRIVING ON SLIPPERY SURFACES .........442
▫ Acceleration ........................ .442
▫ Traction ........................... .442
DRIVING THROUGH WATER .............443
▫ Flowing/Rising Water ..................443
▫ Shallow Standing Water .................443
 OFF-ROAD DRIVING TIPS ...............445
▫ After Driving Off-Road .................445
 WINCH USAGE (POWER WAGON ONLY) — IF
EQUIPPED .......................... .446
▫ Things To Know Before Using Your Winch . . . .446
▫ Understanding The Features Of Your Winch . . .448
▫ Winch Accessories ....................450
▫ Operating Your Winch ..................451
▫ Rigging Techniques ....................464
 POWER STEERING .....................466
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STARTING AND OPERATING 337

AXLE LOCKER SYSTEM (POWER WAGON
MODELS ONLY) — IF EQUIPPED
This 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.
The locking axles are controlled by the axle locker switch.
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, the
front and rear axles are unlocked. In the REAR LOCK
418 STARTING AND OPERATING

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 “Starting and Operat-
ing” for further information. 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. NOTE:
Left to right wheel speed difference may be
necessary to allow the axle to fully lock. If the indicator
light is flashing after placing the switch in the REAR
LOCK or FRONT/REAR LOCK position, drive the ve-
hicle in a turn or on loose gravel to expedite the locking
action.
WARNING!
Do not use the locked axle position for normal
driving. A locked front axle is intended for off-road
driving only. Locking the front axle during on-road
driving will reduce the steering ability. This could
cause a collision and you may be seriously injured.
To lock the front axle; move the axle locker switch to
FRONT/REAR LOCK while traveling less than 3 mph
(5 km/h). The indicator light will be solid when the front
axle is locked.
5
STARTING AND OPERATING 419

avoid damage to the environment. You should know
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 first 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
5
STARTING AND OPERATING 433

•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
LIMITED-SLIP DIFFERENTIAL
The 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.5
STARTING AND OPERATING 441

WARNING!(Continued)
•The ABS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
• 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) – If Equipped
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 similarly 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 ESC are in
the “Partial Off” mode. Refer to “Electronic Stability
Control (ESC)” in this section of this manual. This brake
pressure modulation transfers drive torque from slipping
to non-slipping wheels to provide optimal forward trac-
tion.
Brake Assist System (BAS) – If Equipped
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
BAS detects an emergency braking situation by sensing
the rate and amount of brake application and then
applies optimum pressure to the brakes. The system
applies optimum pressure to the brakes in emergency
braking conditions. This can help reduce braking dis-
tances. The BAS complements the ABS. Applying the
brakes very quickly results in the best BAS assistance. To
474 STARTING AND OPERATING

second time to verify that specific torque has been
achieved. Retighten to specifications at 100 miles
(160 km) and after 500 miles (800 km).
It is recommended that wheel stud nuts be kept torqued
to specifications at all times. Torque wheel stud nuts to
specifications at each lubrication interval.
HOISTING
A conventional floor jack may be used at the jacking
locations. Refer to the graphics that show jacking loca-
tions. However, a floor jack or frame hoist must never be
used on any other parts of the underbody.
CAUTION!
Never use a floor jack directly under the differential
housing of a loaded truck or damage to your vehicle
may result.
JUMP-STARTING PROCEDURES
If your vehicle has a discharged battery it can be jump-
started using a set of jumper cables and a battery in
another vehicle or by using a portable battery booster
pack. Jump-starting can be dangerous if done improperly
so please follow the procedures in this section carefully.
NOTE: When using a portable battery booster pack
follow the manufacturer ’s operating instructions and
precautions.
CAUTION!
Do not use a portable battery booster pack or any
other booster source with a system voltage greater
than 12 Volts or damage to the battery, starter motor,
alternator or electrical system may occur.
6
WHAT TO DO IN EMERGENCIES 617

For 1500 Model axles, the fluid level should be even with
the bottom of the fill hole (within 1/4 in (6.4 mm) of edge
of hole) for the FDU215 HD front axle and C235FE rear
axle.
For all 2500/3500 Model axles, the fluid level should be
1/4 in ± 1/4 in (6.4 mm ± 6.4 mm) below the fill hole on
the 9.25 in front and 3/4 in ± 1/4 in (19 mm ± 6.4 mm) on
10.5 in rear axles. The 11.5 in rear axle level should be 1/4
in ± 1/4 in (6.4 mm ± 6.4 mm) below the fill hole.
Drain And Refill
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.NOTE:
The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
components. Operation of the vehicle in water, as may be
encountered in some off-highway types of service, will
require draining and refilling the axle to avoid damage.
Limited-Slip Differentials
1500 Model rear axles equipped with a Limited Slip
Differential require that 5 oz. (148 ml) MOPAR® Limited
Slip Additive be added to the gear lubricant. Refer to
“Fluids, Lubricants, and Genuine Parts” in “Maintaining
Your Vehicle” for further information. The MOPAR®
Limited Slip Additive should be added to the gear
lubricant whenever a fluid change is made to an axle
equipped with a Limited Slip Differential.
2500/3500 Model axles DO NOT REQUIREany limited
slip oil additive (friction modifiers).
664 MAINTAINING YOUR VEHICLE