2021 RAM CHASSIS CAB brakes

138STARTING AND OPERATING
When the parking brake is applied with the
ignition 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.
DIESEL EXHAUST BRAKE
(ENGINE BRAKING)
The purpose of the exhaust brake (engine
braking) feature is to supply negative (braking)
torque from the engine. Typically, the engine
braking is used for, but not limited to, vehicle
towing applications where vehicle braking can
be achieved by the internal engine power,
thereby sparing the mechanical brakes of the
vehicle.
Benefits of the exhaust brake are:
Vehicle driving control.
Reduced brake fade.
Longer brake life.
Faster cab warm-up.
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.
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil -
dren, and do not leave 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.

Be sure the parking brake is fully disen -
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.

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STARTING AND OPERATING139
The exhaust brake feature will only function
when the driver toggles it on by pushing the
exhaust brake button until the "Exhaust Brake
Indicator" is illuminated. Normal (Full Strength)
exhaust brake mode is indicated by a yellow
"Exhaust Brake Indicator".

Exhaust Brake Switch

Once the "Exhaust Brake Indicator” is
illuminated and the vehicle is moving faster
than 5 mph (8 km/h); the exhaust brake will
automatically operate when the driver removes
pressure from the accelerator pedal. Exhaust
braking is most effective when the engine RPM
is higher. The automatic transmission will
downshift more aggressively in TOW/HAUL
mode when the exhaust brake is enabled to
increase brake performance. NOTE:
For optimum braking power it is recommended
to use the exhaust brake while in TOW/HAUL
mode.
The exhaust brake feature can also be used to
reduce the engine warm-up time. To use the
exhaust brake as a warm-up device, the vehicle
must be stopped or moving less than 5 mph
(8 km/h), the "Exhaust Brake Indicator" must be
on, and the coolant temperature must be below
180°F (82°C) and ambient temperature below
60°F (16°C).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.WARNING!

Do not use the exhaust brake feature when
driving in icy or slippery conditions as 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.

CAUTION!

Use of aftermarket exhaust brakes is not
recommended and could lead to engine damage

4

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STARTING AND OPERATING141
IGNITION PARK INTERLOCK

This vehicle is equipped with an Ignition Park
Interlock which requires the transmission to be in
PARK before the ignition can be turned to the OFF
mode. This helps the driver avoid inadvertently
leaving the vehicle without placing the
transmission in PARK. This system also locks the
transmission in PARK whenever the ignition is in
the OFF mode.

NOTE:
The transmission is NOT locked in PARK when
the ignition is in the ACC mode (even though the
engine will be off). Ensure that the transmission
is in PARK, and the ignition is OFF (not in ACC
mode) before exiting the vehicle.
BRAKE/TRANSMISSION SHIFT
I
NTERLOCK (BTSI) SYSTEM
This vehicle is equipped with a BTSI system that
holds the transmission gear selector in PARK
unless the brakes are applied. For vehicles with
8-speed transmission, to shift the transmission
out of PARK, the engine must be running and
the brake pedal must be pressed. The brake
pedal must also be pressed to shift from
NEUTRAL into DRIVE or REVERSE when the
vehicle is stopped or moving at low speeds.
For vehicles with 6-speed transmission, to shift
the transmission out of PARK, the ignition must
be in the ON/RUN mode (engine running or not)
and the brake pedal must be pressed.
The BTSI will timeout if brake pedal is pressed
for three minutes or longer continuously while in
park. It can be reset by releasing the brake for
more then three seconds, then reapplying the
brake pedal or cycling the ignition.
EIGHT-SPEED AUTOMATIC
T
RANSMISSION — IF EQUIPPED
The transmission is controlled using a rotary
electronic gear selector located on the
instrument 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-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).

CAUTION!

Shift into or out of PARK or REVERSE only after
the vehicle has come to a complete stop.

Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
Before shifting into any gear, make sure
your foot is firmly pressing the brake pedal.
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STARTING AND OPERATING151

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.
Overdrive Operation

The automatic transmission includes an
electronically controlled Overdrive (FIFTH and SIXTH
gears). The transmission will automatically shift into
Overdrive if the following conditions are present:

The gear selector is in the DRIVE position.
The transmission fluid has reached an
adequate temperature.
The engine coolant has reached an adequate
temperature.
Vehicle speed is sufficiently high.

The TOW/HAUL switch has not been activated.

The driver is not heavily pressing the accelerator.

Torque Converter Clutch

A feature designed to improve fuel economy has
been included in the automatic transmission on
your vehicle. A clutch within the torque converter
engages automatically at calibrated speeds.
This may result in a slightly different feeling or
response during normal operation in the upper
gears. When the vehicle speed drops or during
some accelerations, the clutch automatically
disengages.

NOTE:
The torque converter clutch will not engage,
until the transmission fluid and engine
coolant are warm (usually after 1 to 3 miles
(2 to 5 km) of driving). Because engine speed
is higher when the torque converter clutch is
not engaged, it may seem as if the transmis
-
sion is not shifting properly when cold; This is
normal. Using the Electronic Range Select
(ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the
transmission is able to shift into and out of
Overdrive.
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.4

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STARTING AND OPERATING167
(Continued)
Adaptive Cruise Control (ACC) Operation
The buttons on the right side of the steering
wheel operate the ACC system.
Adaptive Cruise Control Buttons
Does not always fully recognize
complex driving conditions, which can
result in wrong or missing distance
warnings.

Will bring the vehicle to a complete stop
while following a target vehicle and hold
the vehicle for approximately two seconds
in the stop position. At this point, there will
be an “ACC may cancel soon” chime and
warning to the driver. When ACC is
cancelled, the system will release the
brakes and the driver must take over
braking. The system can be resumed when
the target vehicle drives off by releasing
the brake and pushing the resume button
on the steering wheel.

WARNING! (Continued)
You should switch off the ACC system:
When driving in fog, heavy rain, heavy
snow, sleet, heavy traffic, and complex
driving situations (i.e., in highway construc -
tion zones).
When entering a turn lane or highway off
ramp; when driving on roads that are
winding, icy, snow-covered, slippery, or
have steep uphill or downhill slopes.
When towing a trailer up or down steep
slopes.
When circumstances do not allow safe
driving at a constant speed.
WARNING! (Continued)
1 — Adaptive Cruise Control On/Off Button
2 — Fixed Speed Cruise Control On/Off Button
3 — CANCEL
4 — Distance Button
5 — RES (+)
6 — SET (-)
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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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.

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STARTING AND OPERATING171
To Vary The Speed Setting
To Increase Or Decrease The Set Speed
After setting a speed, you can increase the
set 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 in 5 mph incre -
ments until the button is released. The new
set speed is reflected in the instrument
cluster display.
Metric Speed (km/h)
Pushing the RES (+) button, or SET (-) button
once will result in a 1 km/h speed adjust -
ment. 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 in 10 km/h
increments until the button is released.
The new set speed is reflected in the instru -
ment cluster display. When An ACC Distance Is Also Set: 
When you use the SET (-) button to decel -
erate, if the engine’s braking power does not
slow the vehicle sufficiently to reach the set
speed, the brake system will automatically
slow the vehicle.
 The ACC system applies the brake down to a
full stop when following the vehicle in front.
If your vehicle follows the vehicle in front to
a standstill, your vehicle will release the
brakes two seconds after coming to a
complete stop.
 The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal.
In addition, downshifting may occur while
climbing uphill or descending downhill. This
is normal operation and necessary to main-
tain set speed. When driving uphill and
down -hill, the ACC system will cancel if the
braking temperature exceeds normal range
(over -heated).
Setting The Following Distance In ACC

The specified following distance for Adaptive
Cruise Control (ACC) can be set by varying the
distance setting between four bars (longest),
three bars (long), two bars (medium) and one
bar (short). Using this distance setting and the
vehicle speed, ACC calculates and sets the
distance to the vehicle ahead. This distance
setting displays in the instrument cluster display.
Distance Settings

1 — Longest Distance Setting (Four Bars)
2 — Long Distance Setting (Three Bars)
3 — Medium Distance Setting (Two Bars)
4 — Short Distance Setting (One Bar)
4

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