2021 RAM CHASSIS CAB transmission

152STARTING AND OPERATING
If the vehicle has not been driven for several
days, the first few seconds of operation after
shifting the transmission into gear may seem
sluggish. This is due to the fluid partially
draining from the torque converter into the
transmission. This condition is normal and
will not cause damage to the transmission.
The torque converter will refill within
five seconds after starting the engine.
When To Use TOW/HAUL Mode

When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent
transmission shifting occurs, push the
TOW/HAUL switch to activate TOW/HAUL mode.
This will improve performance and reduce the
potential for transmission overheating or failure
due to excessive shifting. When operating in
TOW/HAUL mode, transmission upshifts are
delayed, and the transmission will automatically
downshift (for engine braking) when the throttle
is closed and/or during steady braking
maneuvers. TOW/HAUL Switch

The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that
TOW/HAUL mode has been activated. Pushing
the switch a second time restores normal
operation. Normal operation is always the
default at engine start-up. If TOW/HAUL mode is
desired, the switch must be pushed each time
the engine is started.
AUXILIARY SWITCHES — IF EQUIPPED
There can be up to six auxiliary switches located
in the lower switch bank of the instrument panel
which can be used to power various electronic
devices and Power Take Off (PTO). If equipped,
it will take the place of the sixth auxiliary switch.
Connections to the switches are found under
the hood in the connectors attached to the
auxiliary Power Distribution Center.

You have the ability to configure the functionality of
the auxiliary switches via the instrument cluster
display. All switches can now be configured for
setting the switch type operation to latching or
momentary, power source of either battery or
ignition, and ability to hold last state across key
cycles.

NOTE:
Holding last state conditions are met when
switch type is set to latching and power source
is set to ignition.

For further information on using the auxiliary
switches, please refer to the Ram Body Builders
Guide by accessing
https://www.ramtrucks.com/
ram-commercial/body-builders-guide.html
and
choosing the appropriate links.

WARNING!

Do not use the TOW/HAUL feature when driving
in icy or slippery conditions. The increased
engine braking can cause the rear wheels to
slide, and the vehicle to swing around with the
possible loss of vehicle control, which may
cause an accident possibly resulting in
personal injury or death.

21_DPF_OM_EN_USC_t.book Page 152

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

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.

21_DPF_OM_EN_USC_t.book Page 160

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

21_DPF_OM_EN_USC_t.book Page 161