cooling Ram 4500 Chassis Cab 2020 Owner's Manual

4

ONBOARD DIAGNOSTIC SYSTEM — OBD II ....... 118
Onboard Diagnostic System (OBD II)
Cybersecurity..............................................118
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS ...................................................... 119
SAFETY
SAFETY FEATURES ............................................ 120
Anti-Lock Brake System (ABS) ................. 120
Electronic Brake Control (EBC) System ...121
AUXILIARY DRIVING SYSTEMS ........................ 129
Forward Collision Warning (FCW) With
Mitigation — If Equipped............................129 Tire Pressure Monitoring System
(TPMS) .....................................................132
OCCUPANT RESTRAINT SYSTEMS .................. 141
Occupant Restraint Systems Features ....141
Important Safety Precautions ...................141Seat Belt Systems ..................................... 142Supplemental Restraint Systems (SRS) ...151Child Restraints ........................................160
Transporting Pets ....................................179
SAFETY TIPS .................................................... 180
Transporting Passengers ..........................180
Exhaust Gas ........................................... 180
Safety Checks You Should Make Inside
The Vehicle ................................................180 Periodic Safety Checks You Should Make
Outside The Vehicle ...................................182
STARTING AND OPERATING
STARTING THE ENGINE — GAS ENGINE .........183
Automatic Transmission............................ 183
Tip Start Feature ....................................... 183Keyless Enter-N-Go — Ignition ................... 184
Normal Starting Using ENGINE START/
STOP Button ............................................ 184 Cold Weather Operation
(Below –22°F Or −30°C) ......................... 187 After Starting .............................................. 187
STARTING THE ENGINE — DIESEL ENGINE .... 187
Automatic Transmission............................ 187
Keyless Enter-N-Go — Ignition ................... 188
Extreme Cold Weather .............................. 190
Normal Starting Procedure — Engine Manifold
Air Temperature Above 66°F (19°C) ....... 191 Starting Procedure — Engine Manifold Air
Temperature 0°F To 66°F
(–18°C to 19°C) ....................................... 191 Starting Procedure — Engine Manifold Air
Temperature Below 0°F (-18°C) .............. 192 Starting Fluids ............................................ 193 NORMAL OPERATION — DIESEL ENGINE ....... 194
Cold Weather Precautions ........................ 194
Engine Idling ............................................. 197
Noise .......................................................... 198
Stopping The Engine ................................. 198Idle Shutdown ............................................ 199
Programmable Maximum Vehicle Speed ..... 199

Operating Precautions .............................. 200
Cooling System Tips .................................. 200
Diesel Particulate Filter (DPF) Manual
Regeneration - If Equipped ....................... 201
ENGINE BLOCK HEATER — IF EQUIPPED ........ 201
ENGINE BREAK-IN RECOMMENDATIONS —
GAS ENGINE ...................................................... 202
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE .................................................. 202
DIESEL EXHAUST BRAKE
(ENGINE BRAKING) ........................................... 203
PARKING BRAKE .............................................. 204
AUTOMATIC TRANSMISSION ........................... 205 Ignition Park Interlock ............................... 206Brake/Transmission Shift Interlock
System ....................................................... 206 Six–Speed Automatic Transmission —
If Equipped ................................................ 207 Eight-Speed Automatic Transmission —
If Equipped ................................................. 213
AUXILIARY SWITCHES — IF EQUIPPED ........... 218

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7
SERVICING AND MAINTENANCE
SCHEDULED SERVICING — GAS ENGINE ....... 329Maintenance Plan......................................330
Heavy Duty Use Of The Vehicle ................. 333
SCHEDULED SERVICING — DIESEL ENGINE .. 334
Oil Change Indicator System —
Cummins Diesel .........................................335 Perform Service Indicator —
Cummins Diesel ........................................335 Maintenance Plan — Cummins
Diesel Engine ............................................336
ENGINE COMPARTMENT ................................ 343
6.4L Engine ...............................................3436.7L Engine ................................................344
Checking Oil Level — Gas Engine .............345
Checking Oil Level — Diesel Engine ..........345
Adding Washer Fluid ................................345Maintenance-Free Battery .......................346
Pressure Washing ......................................346
DEALER SERVICE .............................................. 347
Engine Oil .................................................. 347Engine Oil Filter ........................................349
Engine Air Cleaner Filter .........................349
Air Conditioner Maintenance ................. 351
Accessory Drive Belt Inspection................354Draining Fuel/Water Separator Filter .....354
Engine Mounted Fuel Filter
Replacement ..............................................356 Underbody Mounted Fuel Filter
Replacement ..............................................357 Priming If The Engine Has Run
Out Of Fuel ................................................ 358 Intervention Regeneration Strategy —
Message Process Flow ............................. 359 Diesel Exhaust Fluid .................................. 359Body Lubrication ...................................... 360
Windshield Wiper Blades ........................ 360
Exhaust System ........................................ 362
Cooling System ......................................... 363
Charge Air Cooler — Inter-Cooler .............. 366
Brake System ............................................ 367Automatic Transmission............................ 368
Rear Axle And 4x4 Front Driving Axle Fluid
Level ....................................................... 370 Transfer Case ............................................ 371Noise Control System Required
Maintenance & Warranty ......................... 371
HOISTING ............................................................374
TIRES....................................................................374
Tire Safety Information ........................... 374
Tires — General Information .................... 382
Tire Types ................................................... 386
Spare Tires — If Equipped ....................... 387
Wheel And Wheel Trim Care .................. 389Tire Chains and Traction Devices ............ 390
Tire Rotation Recommendations .............. 391 DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES .................................... 392
Treadwear .................................................. 392
Traction Grades ......................................... 392Temperature Grades ................................. 393
STORING THE VEHICLE .................................. 393
BODYWORK ........................................................ 393 Protection From Atmospheric Agents ..... 393
Body And Underbody Maintenance .......... 394Preserving The Bodywork.......................... 394
INTERIORS ......................................................... 395
Seats And Fabric Parts .............................. 395
Plastic And Coated Parts........................... 396
Leather Parts ............................................. 396
Glass Surfaces .......................................... 396
TECHNICAL SPECIFICATIONS
IDENTIFICATION DATA ...................................... 397Vehicle Identification Number ................. 397
BRAKE SYSTEM ................................................ 397
Hydraulic Brake Assist — If Equipped....... 397
WHEEL AND TIRE TORQUE
SPECIFICATIONS .............................................. 397
Torque Specifications .............................. 398

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62GETTING TO KNOW YOUR VEHICLE
Climate Control Functions
A/C (Air Conditioning)
The Air Conditioning (A/C) button allows the
operator to manually activate or deactivate the
air conditioning system. When the air condi -
tioning system is turned on, cool dehumidified
air will flow through the outlets into the cabin.
For improved fuel economy, press the A/C
button to turn off the air conditioning and manu -
ally adjust the blower and airflow mode settings.
Also, make sure to select only Panel, Bi-Level, or
Floor modes.
NOTE:
For Manual Climate Controls, if the system is
in Mix, Floor or Defrost Mode, the A/C can be
turned off, but the A/C system shall remain
active to prevent fogging of the windows.
If fog or mist appears on the windshield or
side glass, select Defrost mode, and increase
blower speed if needed.
If your air conditioning performance seems
lower than expected, check the front of the
A/C condenser (located in front of the radi -
ator), for an accumulation of dirt or insects.
Clean with a gentle water spray from the front
of the radiator and through the condenser. MAX A/C
MAX A/C sets the control for maximum cooling
performance.
Press and release to toggle between MAX A/C
and the prior settings. The button illuminates
when MAX A/C is on.
In MAX A/C, the blower level and mode position
can be adjusted to desired user settings.
Pressing other settings will cause the MAX A/C
operation to switch to the selected setting and
MAX A/C to exit.
Recirculation
In cold weather, use of Recirculation mode may
lead to excessive window fogging. The Recircu
-
lation feature may be unavailable (button on
the touchscreen greyed out) if conditions exist
that could create fogging on the inside of the
windshield.
On systems with Manual Climate Controls, if
equipped, the Recirculation mode is not
allowed in Defrost mode to improve window
clearing operation. Recirculation is disabled
automatically if this mode is selected.
Attempting to use Recirculation while in this
mode causes the LED in the control button to
blink and then turns off.
Automatic Temperature Control (ATC)
Automatic Operation

1. Push the AUTO button on the faceplate, or the AUTO button on the touchscreen on the
Automatic Temperature Control (ATC)
Panel.

2. Next, adjust the temperature you would like the system to maintain by adjusting the
driver and passenger temperature control
buttons. Once the desired temperature is
displayed, the system will achieve and auto -
matically maintain that comfort level.
3. When the system is set up for your comfort level, it is not necessary to change the
settings. You will experience the greatest
efficiency by simply allowing the system to
function automatically.
NOTE:
It is not necessary to move the temperature
settings for cold or hot vehicles. The system
automatically adjusts the temperature,
mode, and blower speed to provide comfort
as quickly as possible.

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GETTING TO KNOW YOUR VEHICLE63
The temperature can be displayed in U.S. or
Metric units by selecting the U.S./Metric
customer-programmable feature. Refer to
the “Uconnect Settings” in “Multimedia” for
further information.
To provide you with maximum comfort in the
Automatic mode during cold start-ups, the
blower fan will remain on low until the engine
warms up. The blower will increase in speed
and transition into Auto mode.
Manual Operation Override
This system offers a full complement of manual
override features. The AUTO symbol in the front
ATC display will be turned off when the system
is being used in the manual mode.
Operating Tips
NOTE:
Refer to the chart at the end of this section for
suggested control settings for various weather
conditions.
Summer Operation
The engine cooling system must be protected
with a high-quality antifreeze coolant to provide
proper corrosion protection and to protect
against engine overheating. OAT coolant
(conforming to MS.90032) is recommended.
Winter Operation
To ensure the best possible heater and
defroster performance, make sure the engine
cooling system is functioning properly and the
proper amount, type, and concentration of
coolant is used. Use of the Air Recirculation
mode during Winter months is not recom -
mended, because it may cause window fogging.
Vacation/Storage
Before you store your vehicle, or keep it out of
service (i.e., vacation) for two weeks or more,
run the air conditioning system at idle for about
five minutes, in fresh air with the blower setting
on high. This will ensure adequate system lubri -
cation to minimize the possibility of compressor
damage when the system is started again.
Window Fogging
Vehicle windows tend to fog on the inside in
mild, rainy, and/or humid weather. To clear the
windows, select Defrost or Mix mode and
increase the front blower speed. Do not use the
Recirculation mode without A/C for long
periods, as fogging may occur.
CAUTION!
Failure to follow these cautions can cause
damage to the heating elements:
Use care when washing the inside of the
rear window. Do not use abrasive window
cleaners on the interior surface of the
window. Use a soft cloth and a mild
washing solution, wiping parallel to the
heating elements. Labels can be peeled off
after soaking with warm water.
Do not use scrapers, sharp instruments, or
abrasive window cleaners on the interior
surface of the window.
Keep all objects a safe distance from the
window.
2

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84GETTING TO KNOW YOUR INSTRUMENT PANEL
6. Fuel Gauge
The pointer shows the level of fuel in the
fuel tank when the ignition is in the ON/
RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel door is located.
Refer to “Refueling The Vehicle — Gas
Engine” in “Starting And Operating” for
further information. 7. Temperature Gauge
The gauge pointer shows engine coolant
temperature. The pointer positioned
within the normal range indicates that
the engine cooling system is operating
satisfactorily.
The gauge pointer will likely indicate a higher temperature when driving in hot
weather, up mountain grades, or when
towing a trailer. It should not be allowed
to exceed the upper limits of the normal
operating range.
WARNING!
A hot engine cooling system is dangerous.
You or others could be badly burned by steam
or boiling coolant. You may want to call an
authorized dealer for service if your vehicle
overheats. If you decide to look under the
hood yourself, see “Servicing And
Maintenance.” Follow the warnings under the
Cooling System Pressure Cap paragraph.
CAUTION!
Driving with a hot engine cooling system
could damage your vehicle. If the
temperature gauge reads “H,” pull over and
stop the vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops
back into the normal range. If the pointer
remains on the “H,” turn the engine off
immediately and call an authorized dealer for
service.

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86GETTING TO KNOW YOUR INSTRUMENT PANEL
Premium Instrument Cluster Descriptions

1. Tachometer

Indicates the engine speed in revolutions
per minute (RPM x 1000).
2. Instrument Cluster Display
When the appropriate conditions exist, this display shows the instrument cluster
display messages. Refer to “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel” for further informa -
tion.
3. Speedometer
Indicates vehicle speed. 4. Fuel Gauge
The pointer shows the level of fuel in the
fuel tank when the ignition is in the ON/
RUN position.
 The fuel pump symbol points
to the side of the vehicle where
the fuel door is located.
Refer to “Refueling The Vehicle — Gas
Engine” in “Starting And Operating” for
further information.
5. Temperature Gauge
The gauge pointer shows engine coolant temperature. The pointer positioned
within the normal range indicates that
the engine cooling system is operating
satisfactorily.
The gauge pointer will likely indicate a higher temperature when driving in hot
weather, up mountain grades, or when
towing a trailer. It should not be allowed
to exceed the upper limits of the normal
operating range.
WARNING!
A hot engine cooling system is dangerous.
You or others could be badly burned by steam
or boiling coolant. You may want to call an
authorized dealer for service if your vehicle
overheats. If you decide to look under the
hood yourself, see “Servicing And
Maintenance.” Follow the warnings under the
Cooling System Pressure Cap paragraph.
CAUTION!
Driving with a hot engine cooling system
could damage your vehicle. If the
temperature gauge reads “H,” pull over and
stop the vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops
back into the normal range. If the pointer
remains on the “H,” turn the engine off
immediately and call an authorized dealer for
service.

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88GETTING TO KNOW YOUR INSTRUMENT PANEL
DIESEL INSTRUMENT CLUSTER

1. Tachometer

Indicates the engine speed in revolutions
per minute (RPM x 1000).
2. Engine Coolant Temperature
This gauge shows the engine coolant temperature. The gauge pointer will likely
show higher temperatures when driving
in hot weather, up mountain grades, or in
heavy stop and go traffic. If the red
Warning Light turns on while driving,
safely bring the vehicle to a stop, and
turn off the engine. DO NOT operate the
vehicle until the cause is corrected. 3. Instrument Cluster Display
When the appropriate conditions exist,
this display shows the instrument cluster
display messages. Refer to “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel” for further informa -
tion.
4. Oil Pressure Gauge
The pointer should always indicate some oil pressure when the engine is running.
A continuous high or low reading under
normal driving conditions may indicate a
lubrication system malfunction. Imme -
diate service should be obtained from an
authorized dealer.
WARNING!
A hot engine cooling system is dangerous.
You or others could be badly burned by steam
or boiling coolant. You may want to call an
authorized dealer for service if your vehicle
overheats.
CAUTION!
Driving with a hot engine cooling system
could damage your vehicle. If the
temperature gauge reads greater “H,” pull
over and stop the vehicle. Idle the vehicle
with the air conditioner turned off until the
pointer drops back into the normal range. If
the pointer remains on the “h,” turn the
engine off immediately and call an authorized
dealer for service.

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180SAFETY
SAFETY TIPS
Transporting Passengers
NEVER TRANSPORT PASSENGERS IN THE
CARGO AREA.
Exhaust Gas
The best protection against carbon monoxide
entry into the vehicle body is a properly main -
tained engine exhaust system. Whenever a change is noticed in the sound of
the exhaust system, when exhaust fumes can
be detected inside the vehicle, or when the
underside or rear of the vehicle is damaged,
have a competent mechanic inspect the
complete exhaust system and adjacent body
areas for broken, damaged, deteriorated, or
mispositioned parts. Open seams or loose
connections could permit exhaust fumes to
seep into the passenger compartment. In addi
-
tion, inspect the exhaust system each time the
vehicle is raised for lubrication or oil change.
Replace as required.
Safety Checks You Should Make Inside The
Vehicle
Seat Belts
Inspect the seat belt system periodically,
checking for cuts, frays, and loose parts.
Damaged parts must be replaced immediately.
Do not disassemble or modify the system.
Front seat belt assemblies must be replaced
after a collision. Rear seat belt assemblies must
be replaced after a collision if they have been
damaged (i.e., bent retractor, torn webbing,
etc.). If there is any question regarding seat belt
or retractor condition, replace the seat belt.
WARNING!
Do not leave children or animals inside
parked vehicles in hot weather. Interior
heat build-up may cause serious injury or
death.
It is extremely dangerous to ride in a cargo
area, inside or outside of a vehicle. In a
collision, people riding in these areas are
more likely to be seriously injured or killed.
Do not allow people to ride in any area of
your vehicle that is not equipped with seats
and seat belts.
Be sure everyone in your vehicle is in a seat
and using a seat belt properly.
WARNING!
Exhaust gases can injure or kill. They contain
carbon monoxide (CO), which is colorless and
odorless. Breathing it can make you
unconscious and can eventually poison you.
To avoid breathing (CO), follow these safety
tips:
Do not run the engine in a closed garage or
in confined areas any longer than needed
to move your vehicle in or out of the area.
If you are required to drive with the trunk/
liftgate/rear doors open, make sure that all
windows are closed and the climate control
BLOWER switch is set at high speed. DO
NOT use the recirculation mode.
If it is necessary to sit in a parked vehicle
with the engine running, adjust your
heating or cooling controls to force outside
air into the vehicle. Set the blower at high
speed.

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200STARTING AND OPERATING
Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (anti -
freeze: a mixture of 50% ethylene-glycol and
50% water) must not exceed the normal range
of the temperature gauge 240°F (116°C) with
a 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze)
temperature indicated during operation will be
to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (anti -
freeze) temperature below the normal range on
the gauge 140°F (60°C) can be harmful to the
engine. Low engine coolant (antifreeze)
temperature can cause incomplete combustion
which allows carbon and varnish to form on
piston rings and injector nozzles. Also, the
unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the
engine.
Cooling System Tips
To reduce potential for engine and transmission
overheating in high ambient temperature condi -
tions, take the following actions:
City Driving — When stopped, shift the trans -
mission into NEUTRAL and increase engine
idle speed.
Highway Driving — Reduce your speed.
Up Steep Hills — Select a lower transmission
gear.
Air Conditioning — Turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating
temperature, the minimum oil pressures
required are:
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the
parts fail. Be on the alert for changes in perfor -
mance, sounds, and visual evidence that the
engine requires service. Some important clues
are:
Engine misfiring or vibrating severely.
Sudden loss of power.
Unusual engine noises.
Fuel, oil or coolant leaks.
Sudden change, outside the normal oper -
ating range, in the engine operating tempera -
ture.
Excessive smoke.
Oil pressure drop.
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal
readings, shut the engine off immediately.
Failure to do so could result in immediate and
severe engine damage.

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210STARTING AND OPERATING
If the transmission temperature exceeds
normal operating limits, the powertrain
controller will modify the transmission shift
schedule and expand the range of torque
converter clutch engagement. This is done to
prevent transmission damage due to over -
heating.
If the transmission becomes extremely hot or is
in danger of overheating, the “Transmission
Temperature Warning Light” may illuminate and
the transmission may operate differently until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer
up a steep grade, or in stop-and-go traffic)
during hot weather. In these conditions, torque
converter slip can impose a significant addi -
tional heat load on the cooling system. Down -
shifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to
NEUTRAL (when stopped in heavy traffic) can
help to reduce this excess heat generation. During cold temperatures, transmission opera
-
tion may be modified depending on engine and
transmission temperature as well as vehicle
speed. This feature improves warm up time of
the engine and transmission to achieve
maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmis -
sion fluid is warm (refer to the “Note” under
“Torque Converter Clutch” in this section).
On trucks with AS66RC or AS69RC transmis -
sion, FIFTH and SIXTH gears may be inhibited
briefly on cold starts below 41°F (5°C), and
during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third
gear only. During this condition, the ability of the
vehicle to accelerate under heavily loaded
conditions may be reduced. In all cases, normal
operation will resume once the transmission
temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission remains
in third gear (for AS66RC/AS69RC transmis -
sion) regardless of which forward gear is
selected. If an AS66RC/AS69RC equipped truck enters Limp Home Mode at highway speeds, it
will initially engage fifth gear, until the vehicle
slows to a speed where third gear can be
engaged. PARK, REVERSE, and NEUTRAL will
continue to operate. The Malfunction Indicator
Light (MIL) may be illuminated. Limp Home
Mode allows the vehicle to be driven to an
authorized dealer for service without damaging
the transmission.
In the event of a momentary problem, the trans
-
mission can be reset to regain all forward gears
by performing the following steps:

1. Stop the vehicle.

2. Shift the transmission into PARK.
3. Turn the ignition to the OFF position.
4. Wait approximately 10 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.

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