traction control RAM CHASSIS CAB 2021 Owners Manual

7
Underbody Mounted Fuel Filter
Replacement ..............................................377 Priming If The Engine Has Run Out
Of Fuel .......................................................378 Intervention Regeneration Strategy —
Message Process Flow .............................379 Diesel Exhaust Fluid ..................................379Body Lubrication ........................................380
Windshield Wiper Blades ..........................380
Exhaust System ........................................382
Cooling System .........................................383
Charge Air Cooler — Inter-Cooler ..............386
Brake System ............................................387
Automatic Transmission ............................387
Rear Axle And 4x4 Front Driving Axle
Fluid Level .................................................. 390 Transfer Case ............................................391
Noise Control System Required
Maintenance & Warranty .........................391
TIRES ................................................................... 406
Tire Safety Information .............................406Tires — General Information .....................414 Tire Types ................................................... 418
Spare Tires — If Equipped ......................... 419
Wheel And Wheel Trim Care .................... 421
Snow Traction Devices ............................. 422
Tire Rotation Recommendations .............. 424
DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES .....................................425
Treadwear .................................................. 426
Traction Grades ......................................... 426
Temperature Grades ................................. 426
STORING THE VEHICLE .....................................427
BODYWORK ........................................................ 427
Protection From Atmospheric Agents....... 427
Body And Underbody Maintenance .......... 427Preserving The Bodywork .......................... 428
INTERIORS ......................................................... 428
Seats And Fabric Parts .............................. 428
Plastic And Coated Parts ........................... 429
Leather Surfaces ....................................... 430Glass Surfaces .......................................... 430
TECHNICAL SPECIFICATIONS
VEHICLE IDENTIFICATION NUMBER (VIN) ..... 431
BRAKE SYSTEM ................................................ 431
Hydraulic Brake Assist — If Equipped....... 431
WHEEL AND TIRE TORQUE
SPECIFICATIONS ................................................ 432
Torque Specifications................................ 432
FUEL REQUIREMENTS — GASOLINE
ENGINE ................................................................ 433
6.4L Engine ................................................ 433
Reformulated Gasoline ............................ 433Materials Added To Fuel ........................... 434
Gasoline/Oxygenate Blends .................... 434Do Not Use E-85 In Non-Flex Fuel
Vehicles ...................................................... 434 CNG And LP Fuel System Modifications .. 435Methylcyclopentadienyl Manganese
Tricarbonyl (MMT) In Gasoline .................. 435 Fuel System Cautions................................ 435

21_DPF_OM_EN_USC_t.book Page 7

STARTING AND OPERATING153
(Continued)
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with
either a manually shifted transfer case or an
electronically shifted transfer case.
ELECTRONICALLY SHIFTED TRANSFER
C
ASE (EIGHT SPEED TRANSMISSION) —
I
F EQUIPPED
This is an electronically shifted transfer case
and is operated by the 4WD Control Switch
(Transfer Case Switch), which is located on the
instrument panel.

Four-Position Transfer Case
This electronically shifted transfer case
provides four mode positions:
Two-Wheel Drive High Range (2WD)
Four-Wheel Drive High Range (4WD High)
Four-Wheel Drive Low Range (4WD Low)
N (Neutral)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2WD
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4WD High
Four-Wheel Drive High Range — This range
provides torque to the front driveshaft (engages
four-wheel drive) which allows front and rear
wheels to spin at the same speed. This provides
additional traction for loose, slippery road
surfaces only. 4WD Low

Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maximizes
torque (increased torque over 4WD High) to the
front driveshaft, allowing front and rear wheels to
rotate at the same speed. This range provides
additional traction and maximum pulling power
for loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h) in this range.

N (Neutral)
N (Neutral) — This range disengages both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
WARNING!

You or others could be injured or killed if you
leave the vehicle unattended with the
transfer case in the N (NEUTRAL) position
without first fully engaging the parking brake.
The transfer case N (NEUTRAL) position
disengages both the front and rear drive
shaft from the powertrain, and will allow the
vehicle to roll, even if the transmission is in
PARK. The parking brake should always be
applied when the driver is not in the vehicle.

4

21_DPF_OM_EN_USC_t.book Page 153

154STARTING AND OPERATING
This electronically shifted transfer case is
designed to be driven in the two-wheel drive
position (2WD) for normal street and highway
conditions on dry hard surfaced roads. Driving
the vehicle in two-wheel drive will have greater
fuel economy benefits as the front axle is not
engaged in two-wheel drive.
When additional traction is required, the
transfer case 4WD High and 4WD Low positions
can be used to maximize torque to the front
driveshaft, forcing the front and rear wheels to
rotate at the same speed. This is accomplished
by pushing the desired position on the
four-wheel drive control switch.
For specific shifting instructions Ú page 159.
The 4WD High and 4WD Low positions are
designed for loose, slippery road surfaces only.
Driving in the 4WD High and 4WD Low positions
on dry, hard surfaced roads may cause increased
tire wear and damage to the driveline
components.

NOTE:

The transfer case Neutral button is located in the
center of the four-wheel drive Control Switch and
is pushed by using a ballpoint pen or similar
object. The transfer case Neutral position is to be
used for recreational towing only

Ú
page 214.

Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(4WD High and 4WD Low) are located in the
instrument cluster and indicate the current and
desired transfer case selection. When you
select a different transfer case position, the
indicator lights will do the following:
If All Of The Following Shift Conditions Are Met:

1. The current position indicator light will turn off.

2. The selected position indicator light will flash until the transfer case completes the
shift. 3. When the shift is complete, the indicator
light for the selected position will stop
flashing and remain on.
If One Or More Of The Following Shift Conditions
Are Not Met:

1. The indicator light for the current position will remain on.

2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift.
NOTE:
Before retrying a selection, make certain that all
the necessary requirements for selecting a new
transfer case position have been met. To retry
the selection, push the current position, wait
five seconds, and retry selection Ú page 159.
The “SVC 4WD Warning Light” monitors the
electronically shifted four-wheel drive system.
If this light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly and that service is required.

The transmission may not engage PARK if
the vehicle is moving. Always bring the
vehicle to a complete stop before shifting to
PARK, and verify that the transmission gear
position indicator solidly indicates PARK (P)
without blinking. Ensure that the vehicle is
completely stopped, and the PARK position
is properly indicated, before exiting the
vehicle.

WARNING! (Continued)

21_DPF_OM_EN_USC_t.book Page 154

STARTING AND OPERATING155
NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. This could
cause damage to driveline components.

When operating your vehicle in 4WD Low, the
engine speed is approximately three times that of
the two-wheel drive or 4WD High positions at a
given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).

Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and
circumference on each wheel. Any difference in
tire size can cause damage to the drivetrain.
Because four-wheel drive provides improved
traction, there is a tendency to exceed safe
turning and stopping speeds. Do not go faster
than road conditions permit.
Shifting Procedure
NOTE:
If any of the requirements to select a new
transfer case position have not been met,
the transfer case will not shift. The position
indicator light for the previous position will
remain on and the newly selected position
indicator light will continue to flash until all
the requirements for the selected position
have been met.
If all the requirements to select a new
transfer case position have been met, the
current position indicator light will turn off,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain on. 2WD To 4WD HIGH

Push the desired position on the four-wheel drive
control switch to shift the transfer case. Shifts
between two-wheel drive and 4WD High can
be done with the vehicle stopped or in motion.
With the vehicle in motion, the transfer case will
engage/disengage faster if you momentarily
release the accelerator pedal after turning the
control switch. If the vehicle is stopped, the
ignition switch must be in the ON position with
the engine either running or off. This shift cannot
be completed if the ignition switch is in the ACC
position.

NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD High if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light
will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
WARNING!
Always engage the parking brake when
powering down the vehicle if the “SVC 4WD
Warning Light” is illuminated. Not engaging
the parking brake may allow the vehicle to roll
which may cause personal injury or death.
4

21_DPF_OM_EN_USC_t.book Page 155

STARTING AND OPERATING157
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2WD
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4WD HIGH
Four-Wheel Drive High Range — This range
maximizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the same
speed. This range provides additional traction
for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive.
It maximizes torque to the front driveshaft,
forcing the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for loose,
slippery road surfaces only. Do not exceed
25 mph (40 km/h). N (Neutral)
N (Neutral) — This range disengages both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
This electronically shifted transfer case is
designed to be driven in the two-wheel drive
position (2WD) for normal street and highway
conditions on dry, hard surfaced roads. When additional traction is required, the
transfer case 4WD High and 4WD Low positions
can be used to maximize torque to the front
driveshaft, forcing the front and rear wheels to
rotate at the same speed. This is accomplished
by rotating the four-wheel drive Control Switch
to the desired position.
For specific shifting instructions Ú
page 159.

The 4WD High and 4WD Low positions are
designed for loose, slippery road surfaces only.
Driving in the 4WD High and 4WD Low positions
on dry hard surfaced roads may cause increased
tire wear and damage to the driveline
components.

NOTE:

The transfer case NEUTRAL button is located on
the lower left hand corner of the four-wheel drive
Control Switch. The transfer case NEUTRAL posi -
tion is to be used for recreational towing only

Ú
page 214.

WARNING!

You or others could be injured or killed if you
leave the vehicle unattended with the transfer
case in the N (NEUTRAL) position without first
fully engaging the parking brake. The transfer
case N (NEUTRAL) position disengages both the
front and rear drive shafts from the powertrain
and will allow the vehicle to roll, even if the
transmission is in PARK. The parking brake
should always be applied when the driver is
not in the vehicle.

4

21_DPF_OM_EN_USC_t.book Page 157

158STARTING AND OPERATING
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights
(four-wheel drive and 4WD Low) are located in
the instrument cluster and indicate the current
and desired transfer case selection. When you
select a different transfer case position, the
indicator lights will do the following:
If All Of The Following Shift Conditions Are Met:

1. The current position indicator light will turn off.

2. The selected position indicator light will flash until the transfer case completes the
shift.
3. When the shift is complete, the indicator light for the selected position will stop
flashing and remain on.
If One Or More Of The Following Shift Conditions
Are Not Met:

1. The indicator light for the current position will remain on.

2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift. NOTE:
Before retrying a selection, make certain that all
the necessary requirements for selecting a new
transfer case position have been met. To retry
the selection, turn the control switch back to the
current position, wait five seconds, and retry
selection Ú
page 159.
The “SVC 4WD Warning Light” monitors the
electronically shifted four-wheel drive system.
If this light remains on after engine start up or
illuminates during driving, it means that the
four-wheel drive system is not functioning
properly and that service is required. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can
cause damage to driveline components.

When operating your vehicle in 4WD Low, the
engine speed is approximately three times that of
the two-wheel drive or 4WD High positions at a
given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).

Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and
circumference on each wheel. Any difference in
tire size can cause damage to the drivetrain.
Because four-wheel drive provides improved
traction, there is a tendency to exceed safe
turning and stopping speeds. Do not go faster
than road conditions permit.
WARNING!
Always engage the parking brake when
powering down the vehicle if the “SVC 4WD
Warning Light” is illuminated. Not engaging
the parking brake may allow the vehicle to
roll, which may cause personal injury.

21_DPF_OM_EN_USC_t.book Page 158

STARTING AND OPERATING159
Shifting Procedure
NOTE:

If any of the requirements to select a new
transfer case position have not been met, the
transfer case will not shift. The position indi -
cator light for the previous position will remain
ON and the newly selected position indicator
light will continue to flash until all the require -
ments for the selected position have been
met. To retry a shift: return the control switch
back to the original position, make certain all
shift requirements have been met, wait five
seconds and try the shift again.

If all the requirements to select a new
transfer case position have been met, the
current position indicator light will turn OFF,
the selected position indicator light will flash
until the transfer case completes the shift.
When the shift is complete, the position indi -
cator light for the selected position will stop
flashing and remain ON. 2WD To 4WD HIGH

Push the desired position on the four-wheel drive
control switch to shift the transfer case. Shifts
between two-wheel drive and 4WD High can
be done with the vehicle stopped or in motion.
With the vehicle in motion, the transfer case will
engage/disengage faster if you momentarily
release the accelerator pedal after turning the
control switch. If the vehicle is stopped, the
ignition switch must be in the ON position with
the engine either running or off. This shift cannot
be completed if the ignition switch is in the ACC
position.

NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD High if the front and/or
rear wheels are spinning (no traction). In this
situation, the selected position indicator light
will flash and the original position indicator light
will remain on. At this time, reduce speed and
stop spinning the wheels to complete the shift.
2WD Or 4WD HIGH To 4WD LOW
NOTE:
When shifting into or out of 4WD Low some gear
noise may be heard. This noise is normal and is
not detrimental to the vehicle or occupants.
Shifting can be performed with the vehicle
rolling 2 to 3 mph (3 to 5 km/h) or completely
stopped. You can use either of the following
procedures:
Preferred Procedure

1. With the engine running, slow the vehicle
to 2 to 3 mph (3 to 5 km/h).

2. Shift the transmission into NEUTRAL.
3. While still rolling, push the desired position on the transfer case control switch.
4. After the desired position indicator light is on (not flashing), shift the transmission
back into gear.
4

21_DPF_OM_EN_USC_t.book Page 159

160STARTING AND OPERATING
Alternate Procedure

1. Bring the vehicle to a complete stop.

2. With the ignition switch in the ON position
and the engine running, shift the
transmission into NEUTRAL.
3. Push the desired position on the transfer case control switch.
4. After the desired position indicator light is on (not flashing), shift the transmission
back into gear.
NOTE:
If Steps 1 or 2 of either the Preferred or Alter -
nate Procedure are not satisfied prior to
attempting the shift, then the desired posi -
tion indicator light will flash continuously
while the original position indicator light is
on, until all requirements have been met.
The ignition switch must be in the ON position
for a shift to take place and for the position
indicator lights to be operable. If the ignition
switch is not in the ON position, the shift will
not take place and no position indicator lights
will be on or flashing.
MANUALLY SHIFTED TRANSFER CASE —
I
F EQUIPPED
The transfer case provides four mode positions:
Two-Wheel Drive High Range (2H)
Four-Wheel Drive Lock High Range (4H)
N (Neutral)
Four-Wheel Drive Low Range (4L)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2H
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry, hard
surfaced roads.
4H
Four-Wheel Drive Lock High Range — This range
locks the front and rear driveshafts together
forcing the front and rear wheels to rotate at
the same speed. Additional traction for loose,
slippery road surfaces only. N (Neutral)
N (Neutral) — This range disengages both the
front and rear driveshafts from the powertrain.
To be used for flat towing behind another
vehicle Ú
page 214.
4L
Four-Wheel Drive Low Range — This range locks
the front and rear driveshafts together forcing
the front and rear wheels to rotate at the same
speed. Additional traction and maximum pulling
power for loose, slippery road surfaces only.
Do not exceed 25 mph (40 km/h).
This transfer case is intended to be driven in
the 2H position for normal street and highway
conditions such as dry, hard surfaced roads.
When additional traction is required, the 4H and
4L positions can be used to lock the front and
rear driveshafts together and force the front
and rear wheels to rotate at the same speed.
This is accomplished by simply moving the gear
selector to the desired positions once the
appropriate speed and gear requirements are
met Ú page 159.

21_DPF_OM_EN_USC_t.book Page 160

162STARTING AND OPERATING
NOTE:
Pausing in transfer case N (Neutral) in vehi -
cles equipped with an automatic transmis -
sion may require shutting the engine OFF to
avoid gear clash while completing the shift. If
difficulty occurs, shift the transmission into
Neutral, hold your foot on the brake, and turn
the engine OFF. Complete the range shift to
the desired mode.

Shifting into or out of 4L is possible with the
vehicle completely stopped, however difficulty
may occur due to the mating clutch teeth not
being properly aligned. Several attempts may
be required for clutch teeth alignment and
shift completion to occur. The preferred
method is with the vehicle rolling 2 to 3 mph
(3 to 5 km/h). Avoid attempting to engage or
disengage 4L with the vehicle moving faster
than 2 to 3 mph (3 to 5 km/h).

Do not attempt to shift into or out of 4L while
the transmission is in gear.
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in
the instrument cluster is used to alert the driver
that the front axle is fully engaged and all four
wheels are driving.
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
performs similarly 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 momentary
application of the parking brake may be
necessary to gain maximum traction.
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.
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.

21_DPF_OM_EN_USC_t.book Page 162

170STARTING AND OPERATING
The gear selector is removed from the DRIVE
position.
The Electronic Stability Control/Traction
Control System (ESC/TCS) activates.
The vehicle parking brake is applied.
Driver seat belt is unbuckled at low speeds.
Driver door is opened at low speeds.
A Trailer Sway Control (TSC) event occurs.
The driver switches ESC to Full Off mode.
The braking temperature exceeds normal
range (overheated).
The trailer brake is applied manually
(if equipped).
The following conditions will only cancel the ACC
system:
Driver seat belt is unbuckled at low speeds
Driver door is opened at low speeds
To Turn Off
The system will turn off and clear the set speed
in memory if:
The Adaptive Cruise Control (ACC) on/off
button is pushed
The Fixed Speed Cruise Control on/off button
is pushed
The ignition is placed in the OFF position
4WD Low is engaged
To Resume
If there is a set speed in memory push the RES
(+) button and then remove your foot from the
accelerator pedal. The instrument cluster
display will display the last set speed.
Resume can be used at any speed above
20 mph (32 km/h) when only Fixed Speed
Cruise Control is being used.
Resume can be used at any speed above 0 mph
(0 km/h) when ACC is active. NOTE: 
While in ACC mode when the vehicle comes
to a complete stop longer than two seconds,
the system will cancel. The driver will have
to apply the brakes to keep the vehicle at a
standstill.
 ACC cannot be resumed if there is a
stationary vehicle in front of your vehicle in
close proximity.
WARNING!
The Resume function should only be used if
traffic and road conditions permit. Resuming
a set speed that is too high or too low for
prevailing traffic and road conditions could
cause the vehicle to accelerate or decelerate
too sharply for safe operation. Failure to
follow these warnings can result in a collision
and death or serious personal injury.

21_DPF_OM_EN_USC_t.book Page 170