wheel Ram 4500 Chassis Cab 2020 Service Manual

204STARTING AND OPERATING
(Continued)
Automatic “Smart” Exhaust Brake
Automatic “Smart” Exhaust Brake technology
delivers smoother, less aggressive exhaust
braking characteristics during downhill
descents. Although it can apply full exhaust
braking force if needed, Automatic “Smart”
Exhaust Brake may not apply obvious braking if
the vehicle speed is not increasing. Automatic
“Smart” Exhaust Brake is intended to maintain
vehicle speed, while Full Exhaust Brake is
intended to reduce vehicle speed.
Automatic “Smart” Exhaust Brake can be
enabled by pushing the exhaust brake button
(on the center stack) again anytime after the
normal Full Exhaust Brake has been turned on.
The “Exhaust Brake Indicator” in the instrument
cluster display will change from Yellow to Green
when Automatic “Smart” Exhaust Brake is
enabled. Pushing the exhaust brake button
again will toggle the exhaust brake mode to off.
PARKING BRAKE
Before leaving the vehicle, make sure that the
parking brake is fully applied. Also, be certain to
leave the transmission in PARK.The foot operated parking brake is located
below the lower left corner of the instrument
panel. To apply the park brake, firmly push the
park brake pedal fully. To release the parking
brake, pull the parking brake release handle.

Parking Brake Release

When the parking brake is applied with the igni -
tion switch ON, the “Brake Warning Light” in the
instrument cluster will illuminate.
NOTE:
When the parking brake is applied and the
transmission is placed in gear, the “Brake
Warning Light” will flash. If vehicle speed is
detected, a chime will sound to alert the
driver. Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application.
When parking on a hill, it is important to turn the
front wheels toward the curb on a downhill
grade and away from the curb on an uphill
grade. Apply the parking brake before placing
the gear selector in PARK, otherwise the load on
the transmission locking mechanism may make
it difficult to move the gear selector out of PARK.
The parking brake should always be applied
whenever the driver is not in the vehicle.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply the
parking brake fully when parked to guard
against vehicle movement and possible
injury or damage.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle. Leaving
unattended children in a vehicle is
dangerous for a number of reasons. A child
or others could be seriously or fatally
injured.

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STARTING AND OPERATING207
Six–Speed Automatic Transmission — If
Equipped
Chassis Cab models (with automatic transmis -
sion) may use either the AS66RC or AS69RC
transmission (which are equipped with a Power
Take-Off (PTO) access cover on the side of the
transmission case).
The transmission gear position display (located
in the instrument cluster) indicates the trans -
mission gear range. The gear selector is
mounted on the right side of the steering
column. You must press the brake pedal to
move the gear selector out of PARK (refer to
“Brake/Transmission Shift Interlock System” in
this section). To drive, move the gear selector
from PARK or NEUTRAL to the DRIVE position.
Pull the gear selector toward you when shifting
into REVERSE or PARK, or when shifting out of
PARK.
The electronically-controlled transmission
provides a precise shift schedule. The transmis -
sion electronics are self-calibrating; therefore,
the first few shifts on a new vehicle may be
somewhat abrupt. This is a normal condition,
and precision shifts will develop within a few
hundred miles (kilometers). Only shift from DRIVE to PARK or REVERSE
when the accelerator pedal is released and the
vehicle is stopped. Be sure to keep your foot on
the brake pedal when shifting between these
gears.
The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE shift positions.
Manual downshifts can be made using the Elec
-
tronic Range Select (ERS) shift control. Pushing
the ERS (-/+) switches (on the steering wheel)
while in the DRIVE position will select the
highest available transmission gear, and will
display that gear limit in the instrument cluster
as 1, 2, 3, etc. Refer to "Electronic Range Select
(ERS) Operation" in this section for further infor -
mation. Some models will display both the
selected gear limit, and the actual current gear,
while in ERS mode.
Gear Ranges
Do not depress the accelerator pedal when
shifting from PARK or NEUTRAL into another
gear range. NOTE:
After selecting any gear range, wait a moment
to allow the selected gear to engage before
accelerating. This is especially important when
the engine is cold.
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use
PARK while the vehicle is in motion. Apply the
parking brake when exiting the vehicle in this
range.
When parking on a level surface, you may shift
the transmission into PARK first, and then apply
the parking brake.
When parking on a hill, apply the parking brake
before shifting the transmission to PARK, other
-
wise the load on the transmission locking mech -
anism may make it difficult to move the gear
selector out of PARK. As an added precaution,
turn the front wheels toward the curb on a
downhill grade and away from the curb on an
uphill grade.
5

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208STARTING AND OPERATING
(Continued)
(Continued)
(Continued)
NOTE:
On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
When exiting the vehicle, always:
Apply the parking brake.
Shift the transmission into PARK.
Turn the engine off.
Remove the key fob.
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the gear selector out of PARK with the
brake pedal released. Make sure the trans -
mission is in PARK before exiting the
vehicle.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
Unintended movement of a vehicle could
injure those in or near the vehicle. As with
all vehicles, you should never exit a vehicle
while the engine is running. Before exiting a
vehicle, always come to a complete stop,
then apply the parking brake, shift the
transmission into PARK, turn the engine
OFF, and remove the key fob. When the
ignition is in the LOCK/OFF (key removal)
position (or, with Keyless Enter-N-Go, when
the ignition is in the OFF mode), the trans -
mission is locked in PARK, securing the
vehicle against unwanted movement.
When leaving the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
WARNING! (Continued)
Never leave children alone in a vehicle, or
with access to an unlocked vehicle.
Allowing children to be in a vehicle unat -
tended is dangerous for a number of
reasons. A child or others could be seriously
or fatally injured. Children should be
warned not to touch the parking brake,
brake pedal or the transmission gear
selector.
Do not leave the key fob in or near the
vehicle (or in a location accessible to chil -
dren), and do not leave the ignition (in a
vehicle equipped with Keyless Enter-N-Go)
in the ACC or ON/RUN mode. A child could
operate power windows, other controls, or
move the vehicle.
CAUTION!
Before moving the transmission gear
selector out of PARK, you must turn the igni -
tion to the ON/RUN mode, and also press
the brake pedal. Otherwise, damage to the
gear selector could result.
WARNING! (Continued)

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STARTING AND OPERATING211
NOTE:
Even if the transmission can be reset, we
recommend that you visit your authorized
dealer at your earliest possible convenience.
Your authorized dealer has diagnostic equip -
ment to assess the condition of your trans -
mission.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control
allows the driver to limit the highest available
gear when the transmission is in DRIVE. For
example, if you set the transmission gear limit
to 4 (FOURTH gear), the transmission will not
shift above FOURTH gear, but will shift through
the lower gears normally. You can switch between DRIVE and ERS mode
at any vehicle speed. When the gear selector is
in the DRIVE position, the transmission will
operate automatically, shifting between all
available gears. Tapping the ERS (-) switch will
activate ERS mode, display the current gear in
the instrument cluster, and set that gear as the
top available gear. Once in ERS mode, tapping
(-) or (+) will change the top available gear.

Electronic Range Select
To exit ERS mode, simply push and hold the ERS
(+) switch until the gear limit display disappears
from the instrument cluster.
NOTE:
To select the proper gear position for maximum
deceleration (engine braking), simply push and
hold the ERS (-) switch. The transmission will
shift to the range from which the vehicle can
best be slowed down.
1 — GEAR + Switch
2 — GEAR – Switch
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip and the vehicle
could skid, causing a collision or personal
injury.
CAUTION!
When using ERS for engine braking while
descending steep grades, be careful not to
overspeed the engine. Apply the brakes as
needed to prevent engine overspeed.
5

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STARTING AND OPERATING213
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 opera -
tion. 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.
Eight-Speed Automatic Transmission — If
Equipped
The transmission is controlled using a rotary
electronic gear selector located on the instru -
ment panel. The transmission gear range
(PRND) is displayed both above the gear
selector and in the instrument cluster. To select
a gear range, simply rotate the gear selector.
You must press the brake pedal to shift the transmission out of PARK (or NEUTRAL, when
the vehicle is stopped or moving at low speeds).
To shift past multiple gear ranges at once (such
as PARK to DRIVE), simply rotate the gear
selector to the appropriate detent. Select the
DRIVE range for normal driving.
NOTE:
In the event of a mismatch between the gear
selector position and the actual transmission
gear (for example, driver selects PARK while
driving), the position indicator will blink continu
-
ously until the selector is returned to the proper
position, or the requested shift can be
completed.
The electronically-controlled transmission
adapts its shift schedule based on driver inputs,
along with environmental and road conditions.
The transmission electronics are self-cali -
brating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a
normal condition, and precision shifts will
develop within a few hundred miles (kilome -
ters).
Only shift from DRIVE to PARK or REVERSE
when the accelerator pedal is released and the
vehicle is stopped. Be sure to keep your foot on the brake pedal when shifting between these
gears.
The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE positions.
Manual downshifts can be made using the Elec
-
tronic Range Select (ERS) shift control. Pressing
the GEAR-/GEAR+ switches (on the steering
wheel) while in the DRIVE position will select the
highest available transmission gear, and will
display that gear limit in the instrument cluster
as 1, 2, 3, etc. Refer to “Electronic Range Select
(ERS) Operation” in this section for further infor -
mation. Some models will display both the
selected gear limit, and the actual current gear,
while in ERS mode.

Electronic Transmission Gear Selector

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.
5

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214STARTING AND OPERATING
(Continued)
(Continued)
Gear Ranges
Do not depress the accelerator pedal when
shifting from PARK or NEUTRAL into another
gear range.
NOTE:
After selecting any gear range, wait a moment
to allow the selected gear to engage before
accelerating. This is especially important when
the engine is cold.
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use
PARK while the vehicle is in motion. Apply the
parking brake when exiting the vehicle in this
range.
When parking on a level surface, you may shift
the transmission into PARK first, and then apply
the parking brake.
When parking on a hill, apply the parking brake
before shifting the transmission to PARK. As an
added precaution, turn the front wheels toward
the curb on a downhill grade and away from the
curb on an uphill grade. NOTE:
On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
When exiting the vehicle, always:
Apply the parking brake.
Shift the transmission into PARK.
Turn the engine off.
Remove the key fob.
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the transmission gear selector out of
PARK with the brake pedal released. Make
sure the transmission is in PARK before
exiting the vehicle.
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.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
WARNING! (Continued)

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STARTING AND OPERATING217

1. Stop the vehicle.

2. Shift the transmission into PARK, if
possible. If not, shift the transmission to
NEUTRAL.
3. Push and hold the ignition switch until the engine turns off.
4. Wait approximately 30 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no longer detected, the trans -
mission will return to normal operation.
NOTE:
Even if the transmission can be reset, we
recommend that you visit an authorized dealer
at your earliest possible convenience. An autho -
rized dealer has diagnostic equipment to
assess the condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.Electronic Range Select (ERS) Operation
The Electronic Range Select (ERS) shift control
allows the driver to limit the highest available
gear when the transmission is in DRIVE. For
example, if you set the transmission gear limit
to 4 (FOURTH gear), the transmission will not
shift above FOURTH gear (except to prevent
engine overspeed), but will shift through the
lower gears normally.
You can switch between DRIVE and ERS mode
at any vehicle speed. When the transmission
gear selector is in DRIVE, the transmission will
operate automatically, shifting between all
available gears. Tapping the GEAR – switch (on
the steering wheel) will activate ERS mode,
display the current gear in the instrument
cluster, and set that gear as the top available
gear. Once in ERS mode, tapping the GEAR – or
GEAR + switch will change the top available
gear.
ERS Control

To exit ERS mode, simply push and hold the
GEAR + switch until the gear limit display disap -
pears from the instrument cluster.
1 — GEAR + Switch
2 — GEAR – Switch
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip and the vehicle
could skid, causing a collision or personal
injury.
5

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218STARTING AND OPERATING
When to Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent trans -
mission 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.

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 opera -
tion. 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 PTO (Power Take Off) – If Equipped.
If Power Take Off is 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 function
-
ality of the auxiliary switches via the instrument
cluster display. All switches can now be config -
ured 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 www.rambodybuilder.com
and choosing the appropriate links.
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. Refer to the
operating instructions for your transfer case,
located in this section for further information.
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.

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STARTING AND OPERATING219
Electronically Shifted Transfer Case (Eight
Speed Transmission) — If Equipped
This is an electronic shift transfer case and is
operated by the 4WD Control Switch (Transfer
Case Switch), which is located on the instru -
ment 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 maxi
-
mizes 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. Refer to “Recreational Towing” in this
section for further information.
WARNING!
You or others could be injured or killed if
you leave the vehicle unattended with the
transfer case in the NEUTRAL (N) position
without first fully engaging the parking
brake. The transfer case NEUTRAL (N) posi
-
tion disengages both the front and rear
drive shaft from the powertrain, and will
allow the vehicle to roll, even if the trans -
mission is in PARK. The parking brake
should always be applied when the driver is
not in the vehicle.
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.
5

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220STARTING 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 2WD will have greater fuel
economy benefits as the front axle is not
engaged in 2WD.
When additional traction is required, the
transfer case 4WD HIGH and 4WD LOW posi -
tions 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 4WD control switch.
Refer to “Shifting Procedure” in this section for
specific shifting instructions.
The 4WD HIGH and 4WD LOW positions are
designed for loose, slippery road surfaces only.
Driving in the 4WD HIGH and 4WD LOW posi -
tions 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 4WD 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. Refer to
“Recreational Towing” in “Starting And Oper
-
ating” for further information.
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. To find the
shift requirements, refer to the “Shifting Proce-
dure” for your transfer case, located in this
section.
The “SVC 4WD Warning Light” monitors the
electronic shift four-wheel drive system. If this
light remains on after engine start up or illumi -
nates during driving, it means that the
four-wheel drive system is not functioning prop -
erly and that service is required.

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