2019 Ram 1500 differential

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 applying the
brake of the appropriate wheel(s) to assist in counteracting
the oversteer or understeer condition. Engine 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 match
the 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
road conditions. ESC cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
(Continued)
5
SAFETY 203

ACTIVE-LEVEL FOUR CORNER AIR SUSPENSION
SYSTEM (REBEL MODELS ONLY) —
IF EQUIPPED ......................... .328
▫ Description .......................... .328
▫ Air Suspension Modes ...................331
▫ Instrument Cluster Display Messages .........332
▫ Operation ........................... .332
 AXLE LOCKER SYSTEM — IF EQUIPPED ......334
 LIMITED-SLIP DIFFERENTIAL — IF EQUIPPED .335
 POWER STEERING ...................... .336
▫ Electric Power Steering ..................336
 FUEL SAVER TECHNOLOGY 5.7L ENGINES
ONLY — IF EQUIPPED ....................337
 STOP/START SYSTEM — IF EQUIPPED .......337
▫ Automatic Mode ...................... .337
▫ Possible Reasons The Engine Does Not
Autostop ............................ .338
▫ To Start The Engine While In Autostop Mode . . .338 ▫
To Manually Turn Off The Stop Start System . . .339
▫ To Manually Turn On The Stop Start System. . . .340
▫ System Malfunction .....................340
 SPEED CONTROL — IF EQUIPPED ..........340
▫ To Activate .......................... .341
▫ To Set A Desired Speed ...................341
▫ To Vary The Speed Setting ................341
▫ To Accelerate For Passing .................343
▫ To Resume Speed ..................... .343
▫ To Deactivate ........................ .343
 ADAPTIVE CRUISE CONTROL (ACC) — IF
EQUIPPED ........................... .343
▫ Adaptive Cruise Control (ACC) Operation .....345
▫ Activating
Adaptive Cruise Control (ACC) .....346
▫ To Activate/Deactivate ...................346
▫ To Set A Desired ACC Speed ...............347
▫ To Cancel ........................... .348
290 STARTING AND OPERATING

•Wheel Alignment Mode – Indicator lamps 2, 3, and 4
will be illuminated. Wheel Alignment Mode is disabled
by driving the vehicle.
AXLE LOCKER SYSTEM — IF EQUIPPED
This vehicle is equipped with an electronically locking rear
differential. This differential, when engaged, mechanically
lock together the axle shafts forcing the wheels to spin at an
equal rate. The locking of the rear differential 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 rear axle on hard surfaced roads. The
ability to steer the vehicle is reduced and damage to
the drivetrain may occur when the axle is 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 Button
334 STARTING AND OPERATING

The locking rear axle is controlled by the AXLE LOCKER
button.
Under normal driving conditions, the rear axle should be
unlocked.
During the command to lock the rear 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.
Operating in 4WD LOW the locker can be engaged up to
40 mph (64 km/h) and will remain engaged throughout the
4WD LOW speed range.
Operating the locker in 2WD, 4WD AUTO, and 4WD
LOCK/HIGH the locker can be engaged up to 20 mph
(32 km/h). While driving with the locker engaged, if speed
exceeds 25 mph (40 km/h), the locker will automatically
disengage, but will automatically reengage at 20 mph
(32 km/h).
NOTE:Left to right wheel speed difference may be neces-
sary to allow the rear axle to fully lock. If the indicator light
is flashing after selecting the rear axle lock mode, drive the
vehicle in a turn or on loose gravel to expedite the locking
action. The axle locker could become torque locked due to side to
side loads on the rear axle. Driving slowly while turning
the steering wheel from a left hand turn to a right hand
turn or driving in REVERSE for a short distance may be
required to release the torque lock and unlock the axles.
To unlock the rear axle; push the AXLE LOCK button. The
AXLE LOCK indicator light will go out when the rear axle
is unlocked.
LIMITED-SLIP DIFFERENTIAL — IF EQUIPPED
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 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
6
STARTING AND OPERATING 335

rear wheel on an excessively slippery surface, slight mo-
mentary application of the parking brake may be necessary
to gain maximum traction.
WARNING!
When servicing vehicles equipped with a limited-slip
or locking 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 and
result in unintended movement.
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.
POWER STEERING
Electric Power Steering
The electric power steering system will give you good
vehicle response and increased ease of maneuverability in
tight spaces. The system will vary its assist to provide light
efforts while parking and good feel while driving. If the electric steering system experiences a fault that prevents it
from providing assist, you will still have the ability to steer
the vehicle manually.
If the Steering icon is flashing, it indicates that the vehicle
needs to be taken to the dealer for service. It is likely the
vehicle has lost power steering assistance.
If the Steering icon is displayed and the “POWER STEER-
ING SYSTEM OVER TEMP” message is displayed on the
instrument cluster screen, they indicate that extreme steer-
ing maneuvers may have occurred which caused an over
temperature condition in the power steering system. Once
driving conditions are safe, pull over and let the vehicle
idle for a few moments until the icon and message turn off.
Refer to “Instrument Cluster Display” in “Getting To Know
Your Instrument Panel” for further information.
If the Steering icon is displayed and the “SERVICE POWER
STEERING – ASSIST OFF” message is displayed the in-
strument cluster screen, they indicate the vehicle needs to
be taken to the dealer for service. Refer to “Instrument
Cluster Display” in “Getting To Know Your Instrument
Panel” for further information.
336 STARTING AND OPERATING

Fluid Level Check
The fluid level is preset at the factory and does not require
adjustment under normal operating conditions. Routine
fluid level checks are not required, therefore the transmis-
sion has no dipstick. An authorized dealer can check your
transmission fluid level using special service tools.
If you notice fluid leakage or transmission malfunction, visit
an authorized dealer immediately to have the transmission
fluid level checked. Operating the vehicle with an improper
fluid level can cause severe transmission damage.
CAUTION!
If a transmission fluid leak occurs, visit an authorized
dealer immediately. Severe transmission damage may
occur. An authorized dealer has the proper tools to
adjust the fluid level accurately.
Fluid And Filter Changes
Under normal operating conditions, the fluid installed at
the factory will provide satisfactory lubrication for the life
of the vehicle.
Routine fluid and filter changes are not required. However,
change the fluid and filter if the fluid becomes contaminated
(with water, etc.), or if the transmission is disassembled for
any reason.
Rear Axle And 4x4 Front Driving Axle Fluid Level
For normal service, periodic fluid level checks are not
required. When the vehicle is serviced for other reasons the
exterior surfaces of the axle assembly should be inspected.
If gear oil leakage is suspected inspect the fluid level. Refer
to “Fluids And Lubricants” in “Technical Specifications”
for further information. This inspection should be made
with the vehicle in a level position.
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 front
axle and rear axle.
Lubricant Selection
Refer to “Fluids And Lubricants” in “Technical Specifica-
tion” 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
Rear axles equipped with a Limited Slip Differential re-
quire that 5 oz. (148 ml) Mopar Limited Slip Additive be
8
SERVICING AND MAINTENANCE 521

added to the gear lubricant. Refer to “Fluids And Lubri-
cants” 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.
NOTE:When refilling a limited slip differential axle which
requires a friction modification additive, the additive
should be added before the gear lubricant to ensure 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” in this section for the
proper maintenance intervals.
HOISTING
A conventional floor jack may be used at the jacking
locations. Refer to the graphics that show jacking locations.
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.
TIRES
Tire Safety Information
Tire safety information will cover aspects of the following
information: Tire Markings, Tire Identification Numbers,
Tire Terminology and Definitions, Tire Pressures, and Tire
Loading.
522 SERVICING AND MAINTENANCE

Chart, Tire Sizing.......................... .524
Check Engine Light (Malfunction Indicator Light). . . .195
Checking Your Vehicle For Safety ...............284
Checks, Safety ............................ .284
Child Restraint ........................... .263
Child Restraints Booster Seats ........................... .267
Child Seat Installation ..................277, 278
How To Stow An unused ALR Seat Belt ........276
Infant And Child Restraints .................265
Locating The LATCH Anchorages .............273
Lower Anchors And Tethers For Children .......269
Older Children And Child Restraints ...........266
Seating Positions ........................ .268
Clean Air Gasoline ........................ .559
Cleaning Wheels ............................... .542
Climate Control ............................80
Automatic ..............................84
Manual ................................80
Cold Weather Operation ..................... .299
Compact Disc (CD) Maintenance ................671
Compact Spare Tire ........................ .540
Contract, Service .......................... .676
Cooling Pressure Cap (Radiator Cap) ............516Cooling System
........................... .513
Adding Coolant (Antifreeze) .................515
Coolant Level ....................513, 516, 517
Cooling Capacity ........................ .563
Disposal Of Used Coolant ..................516
Drain, Flush, And Refill ....................514
Inspection ......................... .516, 517
Points To Remember ..................... .518
Pressure Cap ........................... .516
Radiator Cap .......................... .516
Selection Of Coolant (Antifreeze) .......514, 563, 564
Corrosion Protection ....................... .547
Cr

uise Control (Speed Control) .................343
Cruise Light .......................... .192, 193
Cupholders .............................. .125
Customer Assistance ....................... .674
Cybersecurity ............................ .570
Daytime Running Lights ......................69
Dealer Service ............................ .498
Defroster, Rear Window .......................80
Defroster, Windshield .....................80, 286
Delay (Intermittent) Wipers ....................77
Diagnostic System, Onboard ...................194
Differential, Limited Slip .....................335
682 INDEX