transmission RAM CHASSIS CAB 2021 Workshop Manual

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)

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156STARTING AND OPERATING
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. 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.
ELECTRONICALLY SHIFTED TRANSFER
C
ASE (SIX SPEED TRANSMISSION) — IF
E
QUIPPED
The electronically shifted transfer case is
operated by the four-wheel drive Control Switch
(Transfer Case Switch), which is located on the
instrument panel.

Four-Position/On-Demand 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)

21_DPF_OM_EN_USC_t.book Page 156

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

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.

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STARTING AND OPERATING161
The 4H and 4L positions are intended for loose,
slippery road surfaces only. Driving in the 4H
and 4L positions on dry, hard surfaced roads
may cause increased tire wear and damage to
the driveline components.
The “Transfer Case Position Indicator Light” in
the instrument cluster will alert the driver that
the vehicle is in four-wheel drive and that the
front and rear driveshafts are locked together.
This light will illuminate when the transfer case
is shifted into either the 4H or 4L position. There
is no light for the 2H or N (Neutral) positions on
some models.
When operating your vehicle in 4L, the engine
speed is approximately three times that of the
4H or 4L 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
will adversely affect shifting and can cause
damage to the drivetrain. 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.
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.
NOTE:
Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or
uneven tire pressures, excessive vehicle
loading, or cold temperatures.Shifting Procedure — Manually Shifted
Transfer Case
2H To 4H
Shifting between 2H and 4H can be made with
the vehicle stopped or in motion. If the vehicle
is in motion, shifts can be made up to 55 mph
(88 km/h). With the vehicle in motion, the
transfer case will engage/disengage faster if
you momentarily release the accelerator pedal
after completing the shift. Apply a constant
force when shifting the transfer case lever.
2WD High Or 4WD High To 4WD Low
NOTE:
When shifting into or out of 4L some gear noise
may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
With the vehicle rolling at 2 to 3 mph (3 to
5 km/h), shift the transmission into NEUTRAL.
While the vehicle is coasting at 2 to 3 mph (3 to
5 km/h), shift the transfer case lever firmly to
the desired position. Do not pause in transfer
case Neutral.
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

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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

STARTING AND OPERATING163
POWER TAKE OFF (PTO) OPERATION — IF
EQUIPPED

This vehicle when equipped with PTO Prep and
the AS66RC/AS69RC automatic six-speed, will
allow for an aftermarket upfit with a transmission
driven PTO (power take off). The customer will
have the ability to operate the PTO in either
a “stationary”, “mobile” or “remote” mode.
The vehicles will be factory set to the “stationary”
mode. To select a different mode, or to change
any other PTO setting, you will need to enter the
commercial vehicle menu on the instrument
cluster screen. Details of the PTO selection
modes and further PTO information is available
at the Ram Truck Bodybuilders web site:
https://
www.ramtrucks.com/ram-commercial/
body-builders-guide.html
POWER STEERING
HYDRAULIC POWER STEERING
The standard power steering system will give
you good vehicle response and increased ease
of maneuverability in tight spaces. The system
will provide mechanical steering capability if
power assist is lost.

If for some reason the power assist is interrupted,
it will still be possible to steer your vehicle. Under
these conditions, you will observe a substantial
increase in steering effort, especially at very low
vehicle speeds and during parking maneuvers.

NOTE:
Increased noise levels at the end of the
steering wheel travel are considered normal
and do not indicate that there is a problem
with the power steering system.
Upon initial start-up in cold weather, the
power steering pump may make noise for a
short amount of time. This is due to the cold,
thick fluid in the steering system. This noise
should be considered normal, and it does not
in any way damage the steering system.
Power Steering Fluid Check
Checking the power steering fluid level at a
defined service interval is not required. The fluid
should only be checked if a leak is suspected,
abnormal noises are apparent, and/or the
system is not functioning as anticipated. Check
fluid level when the engine is cold and off.
Coordinate inspection efforts through an
authorized dealer.
CAUTION!
Prolonged operation of the steering system
at the end of the steering wheel travel will
increase the steering fluid temperature and it
should be avoided when possible. Damage to
the power steering pump may occur.
WARNING!
Fluid level should be checked on a level
surface and with the engine off to prevent
injury from moving parts and to ensure
accurate fluid level reading. Do not overfill.
Use only manufacturer's recommended
power steering fluid.
4

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STARTING AND OPERATING165
To Set A Desired Speed
Turn the Cruise Control on. When the vehicle
has reached the desired speed, push the SET (-)
button and release. Release the accelerator
and the vehicle will operate at the selected
speed. Once a speed has been set, a message
“CRUISE CONTROL SET TO MPH (km/h)” will
appear indicating the set speed. A cruise
indicator lamp, along with set speed will also
appear and stay on in the instrument cluster
display when the speed is set.
NOTE:
The vehicle should be traveling at a steady
speed and on level ground before pushing the
SET (-) button.
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
When Cruise Control is set, you can increase
the speed by pushing the RES (+) button, or
decrease speed by pushing the SET (-) button.
U.S. Speed (mph)
Pushing the RES (+) button, or SET (-) button
once will result in a 1 mph speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 mph.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
Metric Speed (km/h)
Pushing the RES (+), or SET (-) button once
will result in a 1 km/h speed adjustment.
Each subsequent tap of the button results in
an adjustment of 1 km/h.
If the button is continually pushed, the set
speed will continue to adjust until the button
is released, then the new set speed will be
established.
To Accelerate For Passing
While the Cruise Controls is set, press the
accelerator as you would normally. When the
pedal is released, the vehicle will return to the
set speed.
Using Cruise Control On Hills
The transmission may downshift on hills to
maintain the vehicle set speed.
The Cruise Control system maintains speed up
and down hills. A slight speed change on
moderate hills is normal. On steep hills, a greater speed loss or gain may occur so it may
be preferable to drive without Cruise Control.
To Resume Speed
To resume a previously set speed, push the
RES (+) button and release. Resume can be
used at any speed above 20 mph (32 km/h).
To Deactivate
A soft tap on the brake pedal, pushing the
CANCEL button, or normal brake pressure while
slowing the vehicle will deactivate the Cruise
Control without erasing the set speed from
memory.
WARNING!
Cruise Control can be dangerous where the
system cannot maintain a constant speed.
Your vehicle could go too fast for the
conditions, and you could lose control and
have an accident. Do not use Cruise Control
in heavy traffic or on roads that are winding,
icy, snow-covered or slippery.
4

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168STARTING AND OPERATING
Adaptive Cruise Control (ACC) Menu
The instrument cluster display will show the
current ACC system settings. The information it
displays depends on ACC system status.
Push the ACC on/off button until one of the
following appears in the instrument cluster
display:
Adaptive Cruise Control Off
When ACC is deactivated, the display will read
“Adaptive Cruise Control Off.”
Adaptive Cruise Control Ready
When ACC is activated, but the vehicle speed
setting has not been selected, the display will
read “Adaptive Cruise Control Ready.”
Adaptive Cruise Control Set
When the RES (+) or the SET(-) button is pushed,
the display will read “ACC SET.”
When ACC is set, the set speed will show in the
instrument cluster display.
The ACC screen may display once again if any of
the following ACC activity occurs:
System Cancel
Driver Override
System Off
ACC Proximity Warning
ACC Unavailable Warning
The instrument cluster display will return to the
last display selected after five seconds of no
ACC display activity.
Activating Adaptive Cruise Control (ACC)
The minimum set speed for the ACC system is
20 mph (32 km/h).
When the system is turned on and in the ready
state, the instrument cluster display will read
“ACC Ready.”
When the system is off, the instrument cluster
display will read “Adaptive Cruise Control (ACC)
Off.”
NOTE:
You cannot engage ACC under the following
conditions:
When in 4WD Low
When brakes are applied
When the parking brake is applied
When the automatic transmission is in PARK,
REVERSE or NEUTRAL
When the vehicle speed is below the
minimum speed range
When the brakes are overheated
When the driver’s door is open at low speeds
When the driver’s seat belt is unbuckled at
low speed
Electronic Stability Control (ESC) Full Off
mode is active
To Activate/Deactivate
Push and release the Adaptive Cruise Control
(ACC) on/off button. The ACC menu in the
instrument cluster displays “ACC Ready.”
To turn the system off, push and release the
Adaptive Cruise Control (ACC) on/off button
again. At this time, the system will turn off
and the instrument cluster display will show
“Adaptive Cruise Control (ACC) Off.”

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