2021 RAM CHASSIS CAB radiator

386SERVICING AND MAINTENANCE
Checking Coolant Level — 6.4L Engine
The level of the coolant in the pressurized
coolant bottle should be between the “MIN” and
“MAX” range on the bottle when the engine is
cold.

The radiator normally remains completely full,
so there is no need to remove the cap unless
checking for coolant freeze point or replacing
engine coolant (antifreeze). Advise your service
attendant of this. As long as the engine operating
temperature is satisfactory, the coolant bottle
need only be checked once a month. When
additional engine coolant is needed to maintain
the proper level, it should be added to the coolant
bottle. Do not overfill.

Cooling System Notes
NOTE:
When the vehicle is stopped after a few miles/
kilometers of operation, you may observe vapor
coming from the front of the engine compart -
ment. This is normally a result of moisture from
rain, snow, or high humidity accumulating on
the radiator and being vaporized when the ther -
mostat opens, allowing hot engine coolant (anti -
freeze) to enter the radiator. If an examination of your engine compartment
shows no evidence of radiator or hose leaks,
the vehicle may be safely driven. The vapor will
soon dissipate.
Do not overfill the coolant expansion bottle.
Check the coolant freeze point in the radiator
and in the coolant expansion bottle. If engine
coolant (antifreeze) needs to be added, the
contents of the coolant expansion bottle
must also be protected against freezing.
If frequent engine coolant additions are
required, the cooling system should be pres
-
sure tested for leaks.
Maintain engine coolant concentration at a
minimum of 50% OAT coolant (conforming to
MS.90032) and distilled water for proper
corrosion protection of your engine which
contains aluminum components.
Make sure that the coolant expansion bottle
overflow hoses are not kinked or obstructed.
Keep the front of the radiator clean. If your
vehicle is equipped with air conditioning,
keep the front of the condenser clean.
Do not change the thermostat for Summer or
Winter operation. If replacement is ever
necessary, install ONLY the correct type ther -
mostat. Other designs may result in unsatis -
factory engine cooling performance, poor gas
mileage, and increased emissions.
CHARGE AIR COOLER — INTER-COOLER

The charge air cooler is positioned below the
radiator and the air conditioner condenser. Air
enters the engine through the air cleaner and
passes through the turbocharger, where it is
pressurized. This pressurized air rapidly reaches
high temperature. The air is then directed
through a hose to the charge air cooler and
through another hose to the intake manifold of
the engine. The air entering the engine has been
cooled by about 50° to 100°F (10° to 38°C).
This cooling process enables more efficient
burning of fuel resulting in fewer emissions.

To guarantee optimum performance of the
system, keep the surfaces of the charge air
cooler, condenser and radiator clean and free
of debris. Periodically check the hoses leading
to and from the charge air cooler for cracks or
loose clamps resulting in loss of pressure and
reduced engine performance.

21_DPF_OM_EN_USC_t.book Page 386

TECHNICAL SPECIFICATIONS443
(Continued)
CAUTION!
Mixing of engine coolant (antifreeze) other
than specified Organic Additive Technology
(OAT) engine coolant (antifreeze), may
result in engine damage and may decrease
corrosion protection. Organic Additive Tech -
nology (OAT) engine coolant is different and
should not be mixed with Hybrid Organic
Additive Technology (HOAT) engine coolant
(antifreeze) or any “globally compatible”
coolant (antifreeze). If a non-OAT engine
coolant (antifreeze) is introduced into the
cooling system in an emergency, the
cooling system will need to be drained,
flushed, and refilled with fresh OAT coolant
(conforming to MS.90032), by an autho -
rized dealer as soon as possible.Do not use water alone or alcohol-based
engine coolant (antifreeze) products. Do
not use additional rust inhibitors or antirust
products, as they may not be compatible
with the radiator engine coolant and may
plug the radiator.
This vehicle has not been designed for use
with propylene glycol-based engine coolant
(antifreeze). Use of propylene glycol-based
engine coolant (antifreeze) is not recom -
mended.
CAUTION! (Continued)
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451
Belts, Seat
..................................................... 330Bluetooth Connecting To A Particular Mobile Phone Or Audio Device After Pairing
................262Body Builders Guide........................................ 10Body Mechanism Lubrication........................ 380B-Pillar Location............................................. 411Brake Assist System...................................... 274Brake Control System.................................... 274Brake Fluid.......................................... 387, 444Brake System...................................... 387, 431Fluid Check............................................... 387Master Cylinder......................................... 387Parking...................................................... 137Warning Light............................................ 107Brake/Transmission Interlock....................... 141Bulb Replacement......................................... 401Bulbs, Light.......................................... 332, 401
C
Cab Top Clearance Lights.............................. 405Camera.......................................................... 186Camera, AUX........................................ 188, 194Camera, Rear...................................... 186, 189Capacities, Antifreeze (Engine Coolant)......... 439Capacities, Fluid............................................ 439Caps, FillerOil (Engine)................................................ 364Power Steering.......................................... 163Radiator (Coolant Pressure)...................... 385
Car Washes................................................... 428Carbon Monoxide Warning............................ 333Cargo Light....................................................... 54CD................................................................. 255Cellular Phone.............................................. 269Center High Mounted Stop Light................... 405Center Seat Storage Compartment.................. 67Changing A Flat Tire...................................... 339Charge Air Cooler.......................................... 386Chart, Tire Sizing........................................... 407Check Engine Light (Malfunction
Indicator Light).............................................. 117Checking Your Vehicle For Safety................. 330Checks, Safety.............................................. 330Child Restraint.............................................. 312Child RestraintsBooster Seats........................................... 315Child Seat Installation..................... 323, 325How To Stow An unused ALR Seat Belt.... 322Infant And Child Restraints....................... 313Locating The LATCH Anchorages.............. 320Lower Anchors And Tethers For Children.. 317Older Children And Child Restraints......... 314Seating Positions...................................... 316Clean Air Gasoline......................................... 433CleaningWheels..................................................... 421Climate Control................................................ 58Automatic.................................................... 59Manual........................................................ 62
Cold Weather Operation................................ 122Compact Spare Tire...................................... 419Contract, Service........................................... 446Controls........................................................ 247Cooling Pressure Cap (Radiator Cap)............ 385Cooling System............................................. 383Adding Coolant (Antifreeze)...................... 384Coolant Level................................... 384, 386Cooling Capacity....................................... 439Disposal Of Used Coolant......................... 385Drain, Flush, And Refill............................. 384Inspection................................................. 386Points To Remember................................ 386Pressure Cap............................................ 385Radiator Cap............................................. 385Selection Of Coolant (Antifreeze)..... 384, 440Corrosion Protection..................................... 427Cruise Control (Speed Control)............. 164, 166Cruise Light................................................... 115Customer Assistance.................................... 445Cybersecurity................................................ 220
D
Daytime Running Lights...................................51Dealer Service............................................... 367Defroster, Rear Window...................................62Defroster, Windshield............................ 62, 331Delay (Intermittent) Wipers..............................57Deleting A Phone........................................... 262Diagnostic System, Onboard......................... 116
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456 Power Steering Fluid
...................................... 444Pregnant Women And Seat Belts...................300Preparation For Jacking................................. 339Presets.......................................................... 253PTO (Power Take-Off)..................................... 163
R
Radial Ply Tires.............................................. 416Radiator Cap (Coolant Pressure Cap).. 384, 385Radio Presets...................................................... 253Radio Controls............................................... 247Radio Mode................................................... 247Radio Operation.................................. 247, 269Radio Remote Controls.................................. 247Rain Sensitive Wiper System........................... 58Rear Axle (Differential)......................... 390, 391Rear Camera................................................. 189Rear ParkSense System................................ 177Rear Window, Sliding....................................... 78Recreational Towing...................................... 214Shifting Into Transfer Case Neutral (N)..... 216Shifting Out Of Transfer Case Neutral (N).. 217Reformulated Gasoline.................................. 433Refrigerant.................................................... 372Release, Hood................................................. 79Reminder, Seat Belt...................................... 294Remote Keyless Entry...................................... 15Programming Additional Key Fobs.............. 17Remote Sound System (Radio) Control......... 247
Remote Start (Diesel)...................................... 22Remote Start (Gasoline).................................. 20Remote StartingExit Remote Start Mode.............................. 21Replacement Bulbs...................................... 401Replacement Tires........................................ 417Reporting Safety Defects.............................. 447Resetting Perform Service Indicator............. 358Restraints, Child........................................... 312Restraints, Head.............................................. 38Rotation, Tires.............................................. 424
S
Safety........................................................... 246Safety Checks Inside Vehicle........................ 330Safety Checks Outside Vehicle..................... 332Safety Defects, Reporting............................. 447Safety Features............................................. 246Safety Information, Tire................................ 406Safety Tips.................................................... 330Safety, Exhaust Gas...................................... 333Satellite Radio.............................................. 249Saved Radio Stations................................... 253Schedule, Maintenance................................ 353Seat BeltAutomatic Locking Retractor (ALR)........... 301Seat Belt Reminder....................................... 107Seat Belts............................................ 293, 330Adjustable Shoulder Belt.......................... 297
Adjustable Upper Shoulder Anchorage..... 297Adjustable Upper Shoulder Belt Anchorage............................................ 297Child Restraints........................................ 312Extender................................................... 299Front Seat........................................ 293, 296Inspection................................................. 330Lap/Shoulder Belt Operation.................... 296Lap/Shoulder Belt Untwisting................... 297Operating Instructions.............................. 296Pregnant Women...................................... 300Reminder.................................................. 294Seat Belt Extender.................................... 299Seat Belt Reminder.................................. 294Untwisting Procedure................................ 297Seat Belts Maintenance................................ 429Seats.................................................. 33, 34, 35Adjustment...........................................33, 35Easy Entry....................................................36Folding Floor................................................70Head Restraints...........................................38Memory.......................................................32Power...........................................................35Rear Folding................................................33Tilting...........................................................33Security Alarm........................................ 23, 108Selection Of Coolant (Antifreeze).................. 440Sentry Key (Immobilizer)..................................17Service Assistance........................................ 445Service Contract............................................ 446

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