2018 Ram 2500 Differential

Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, the TCS may
apply brake pressure to the spinning wheel(s) and/or
reduce engine power to provide enhanced acceleration and
stability. A feature of the TCS, Brake Limited Differential
(BLD), 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. BLD may remain enabled even if TCS
and ESC are in a reduced mode.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC corrects
for oversteering or understeering of the vehicle by apply-
ing the brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not matchthe intended path, ESC applies the brake of the appropriate
wheel to assist in counteracting the oversteer or understeer
condition.
•
Oversteer — when the vehicle is turning more than
appropriate for the steering wheel position.
• Understeer — when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” located
in the instrument cluster will start to flash as soon as the
ESC system becomes active. The “ESC Activation/
Malfunction Indicator Light” also flashes when the TCS is
active. If the “ESC Activation/Malfunction Indicator
Light” begins to flash during acceleration, ease up on the
accelerator and apply as little throttle as possible. Be sure to
adapt your speed and driving to the prevailing road
conditions.
WARNING!
• Electronic Stability Control (ESC) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
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5
SAFETY 209

▫Airing Down For Off-Road Driving ..........371
▫ Vehicle Recovery .......................372
▫ After Driving Off-Road ...................375
 LIMITED-SLIP DIFFERENTIAL ..............375
 WINCH USAGE — POWER WAGON ONLY
(IF EQUIPPED) ........................ .376
▫ Things To Know Before Using Your Winch .....376
▫ Understanding The Features Of Your Winch . . . .378
▫ Winch Accessories ..................... .380
▫ Operating Your Winch ...................381
▫ Rigging Techniques .....................391
 POWER STEERING .......................392
▫ Electric Power Steering — 1500 Models .......392
▫ Hydraulic Power Steering —
2500/3500 Models ..................... .393
 FUEL SAVER TECHNOLOGY 5.7L/6.4L ENGINES
ONLY — IF EQUIPPED ....................394
 SPEED CONTROL .......................395 ▫
To Activate .......................... .395
▫ To Set A Desired Speed ...................396
▫ To Vary The Speed Setting ................396
▫ To Accelerate For Passing .................397
▫ To Resume Speed ..................... .397
▫ To Deactivate ........................ .397
 PARKSENSE REAR PARK ASSIST —
IF EQUIPPED ..........................398
▫ ParkSense Sensors ..................... .398
▫ ParkSense Warning Display ................398
▫ ParkSense Display ..................... .398
▫ Enabling And

Disabling ParkSense ..........401
▫ Service The ParkSense Rear Park Assist System. .402
▫ Cleaning The ParkSense System .............402
▫ ParkSense System Usage Precautions .........402
 PARKSENSE FRONT AND REAR PARK ASSIST —
IF EQUIPPED ..........................404
▫ ParkSense Sensors ..................... .404
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STARTING AND OPERATING 285

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 situations
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 possi-
bly cause the vehicle to become stuck.
Axle Lock Selector
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STARTING AND OPERATING 359

The locking axles are controlled by the axle locker switch.
The switch has three positions:
•AXLE UNLOCK – the front and rear axles are unlocked
• REAR LOCK – the rear axle is locked
• FRONT/REAR LOCK – the front and rear axles are
locked
Under normal driving conditions, the switch should be left
in the AXLE UNLOCK position.
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 trac-
tion 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 neces-
sary 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 vehicle 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.
NOTE: The rear axle must be locked before the front axle
will lock.
To unlock the front axle; move the axle locker switch to
REAR LOCK. The FRONT/REAR LOCK indicator light
will go out when the axle is unlocked.
360 STARTING AND OPERATING

Driving Through Water
Extreme care should be taken crossing any type of water.
Water crossings should be avoided if possible and only be
attempted when necessary, in a safe responsible manner.
You should only drive through areas which are designated
and approved. You should tread lightly and 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
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CAUTION!(Continued)
too fast or through too deep of water. Water can cause
permanent damage to engine, driveline or other ve-
hicle components and your brakes will be less effec-
tive once wet and/or muddy.
• Before You Cross Any Type Of Water – As you ap-
proach 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 crossing is the
water depth, current and bottom conditions. On soft
bottoms the vehicle will sink in, effectively increasing
the water level on the vehicle. Be sure to consider this
when determining the depth and the ability to safely
cross.
• Crossing Puddles, Pools, Flooded Areas Or Other
Standing Water – Puddles, pools, flooded or other
standing water areas normally contain murky or muddy
waters. These water types normally contain hidden
obstacles and make it difficult to determine an accurate
370 STARTING AND OPERATING

After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you can
get any problems taken care of right away and have your
vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
• Inspect the radiator for mud and debris and clean as
required.
• Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
• Check for accumulations of plants or brush. These things
could be a fire hazard. They might hide damage to fuel
lines, brake hoses, axle pinion seals, and propeller shafts.
• After extended operation in mud, sand, water, or similar
dirty conditions, have the radiator, fan, brake rotors,
wheels, brake linings, and axle yokes inspected and
cleaned as soon as possible.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might
not have full braking power when you need it to
prevent a collision. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
• 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
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STARTING AND OPERATING 375

driving and cornering, the limited-slip unit performs simi-
larly to a conventional differential. On slippery 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 mo-
mentary 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.
WINCH USAGE — POWER WAGON ONLY (IF
EQUIPPED)
Things To Know Before Using Your Winch
General Winch Information
Your vehicle is equipped with an electric vehicle recovery
winch. This winch uses the electrical power from the
vehicle charging system to power a motor that winds wire
rope into the winch drum via planetary gear reduction. By
nature, a winch is capable of generating very high forces
and should be used with care. Do not operate the winch
without reading and understanding the complete winch
owner’s manual.
Tensioning The Wire Rope
The winch rope must be properly tensioned before use.
Follow the instructions below to tension the rope:
1. Un-spool the wire rope leaving five wraps of rope on the winch drum.
2. Attach the hook to a suitable anchor point.
376 STARTING AND OPERATING

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
And Lubricants” in “Technical Specification” 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).
NOTE: When refilling an axle with a Limited Slip Differ-
ential, (which requires a Limited Slip Additive), the Lim-
ited Slip Additive should be added before the gear lubri-
cant is added to insure proper additive fill.
Drain And Refill
Refer to the “Maintenance Plan” for the proper mainte-
nance intervals.
Transfer Case
Selection Of Lubricant
Use only the manufacturer’s recommended fluid. Refer to
“Fluids And Lubricants” in “Technical Specifications” for
further information.
Fluid Level Check
This fluid level can be checked by removing the filler plug.
The fluid level should be to the bottom edge of the filler
plug hole with the vehicle in a level position.
Drain And Refill
Refer to the “Maintenance Plan” for the proper mainte-
nance intervals.8
SERVICING AND MAINTENANCE 557