2021 RAM CHASSIS CAB cooling

SERVICING AND MAINTENANCE383

Under normal operating conditions, the catalytic
converter will not require maintenance. However,
it is important to keep the engine properly tuned
to ensure proper catalyst operation and prevent
possible catalyst damage.
NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.

In unusual situations involving grossly
malfunctioning engine operation, a scorching
odor may suggest severe and abnormal catalyst
overheating. If this occurs, stop the vehicle, turn off
the engine and allow it to cool. Service, including a
tune-up to manufacturer's specifications, should be
obtained immediately.

To minimize the possibility of catalytic converter
damage:
Do not interrupt the ignition when the trans
-
mission is in gear and the vehicle is in
motion.
Do not try to start the vehicle by pushing or
towing the vehicle.
Do not idle the engine with any ignition
components disconnected or removed, such
as when diagnostic testing, or for prolonged
periods during very rough idle or malfunc -
tioning operating conditions.
COOLING SYSTEM CAUTION!
The catalytic converter requires the use of
unleaded fuel only. Leaded gasoline will
destroy the effectiveness of the catalyst as
an emissions control device and may seri -
ously reduce engine performance and
cause serious damage to the engine.

Damage to the catalytic converter can result
if your vehicle is not kept in proper operating
condition. In the event of engine malfunc -
tion, particularly involving engine misfire or
other apparent loss of performance, have
your vehicle serviced promptly. Continued
operation of your vehicle with a severe
malfunction could cause the converter to
overheat, resulting in possible damage to
the converter and vehicle.

WARNING!

You or others can be badly burned by hot
engine coolant (antifreeze) or steam from your
radiator. If you see or hear steam coming from
under the hood, do not open the hood until the
radiator has had time to cool. Never open a
cooling system pressure cap when the radiator
or coolant bottle is hot.

Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.
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384SERVICING AND MAINTENANCE
Engine Coolant Checks
Check the engine coolant (antifreeze)
protection every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant is dirty or rusty in appearance,
the system should be drained, flushed and
refilled with fresh coolant. Check the front of the
A/C condenser or radiator for any accumulation
of bugs, leaves, etc. If dirty, clean by gently
spraying water from a garden hose vertically
down the face of the A/C condenser or the back
of the radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and
tightness of the connection at the coolant
recovery bottle and radiator. Inspect the entire
system for leaks.
DO NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT.
Cooling System — Drain, Flush And Refill
NOTE:

Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added to
the system please contact an authorized dealer.
If the engine coolant (antifreeze) is dirty or
contains visible sediment, have an authorized
dealer clean and flush with Organic Additive
Technology (OAT) coolant (conforming to
MS.90032).
For the proper maintenance intervals
Ú
page 354.
Selection Of Coolant
For further information Ú page 440.
NOTE:
Mixing of engine coolant (antifreeze) other
than specified Organic Additive Technology
(OAT) engine coolant, may result in engine
damage and may decrease corrosion protec-
tion. OAT engine coolant is different and
should not be mixed with Hybrid Organic
Additive Technology (HOAT) engine coolant
or any “globally compatible” coolant. If a
non-OAT engine coolant 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 authorized dealer as soon
as possible.
Do not use water alone or alcohol-based
engine coolant products. Do not use addi-
tional rust inhibitors or anti-rust 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.
Use of propylene glycol-based engine coolant
is not recommended.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added
to the system please contact an authorized
dealer.
Adding Coolant
Your vehicle has been built with an improved
engine coolant (OAT coolant conforming to
MS.90032) that allows extended maintenance
intervals. This engine coolant (antifreeze)
can be used up to ten years or 150,000 miles
(240,000 km) before replacement. To prevent
reducing this extended maintenance period, it
is important that you use the same engine
coolant (OAT coolant conforming to MS.90032)
throughout the life of your vehicle.

21_DPF_OM_EN_USC_t.book Page 384

SERVICING AND MAINTENANCE385
Please review these recommendations for
using Organic Additive Technology (OAT) engine
coolant that meets the requirements of FCA
Material Standard MS.90032. When adding
engine coolant:

We recommend using Mopar Antifreeze/
Coolant 10 Year/150,000 Mile (240,000 km)
Formula OAT that meets the requirements of
FCA Material Standard MS.90032.

Mix a minimum solution of 50% OAT engine
coolant that meets the requirements of FCA
Material Standard MS.90032 and distilled
water. Use higher concentrations (not to
exceed 70%) if temperatures below −34°F
(−37°C) are anticipated. Please contact an
authorized dealer for assistance.
Use only high purity water such as distilled or
deionized water when mixing the water/
engine coolant solution. The use of lower
quality water will reduce the amount of corro -
sion protection in the engine cooling system.
NOTE:
It is the owner's responsibility to maintain the
proper level of protection against freezing
according to the temperatures occurring in
the area where the vehicle is operated.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added
to the system, please contact a local autho -
rized dealer.
Mixing engine coolant types is not recom -
mended and can result in cooling system
damage. If HOAT and OAT coolant are mixed
in an emergency, have an authorized dealer
drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as
possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss
of engine coolant (antifreeze), and to ensure
that engine coolant will return to the radiator
from the coolant expansion bottle/recovery
tank (if equipped).
The cap should be inspected and cleaned if
there is any accumulation of foreign material on
the sealing surfaces.Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze)
is a regulated substance requiring proper
disposal. Check with your local authorities
to determine the disposal rules for your
community. To prevent ingestion by animals or
children, do not store ethylene glycol-based
coolant in open containers or allow it to remain
in puddles on the ground, clean up any ground
spills immediately. If ingested by a child or pet,
seek emergency assistance immediately.
WARNING!
Do not open hot engine cooling system.
Never add engine coolant (antifreeze) when
the engine is overheated. Do not loosen or
remove the cap to cool an overheated
engine. Heat causes pressure to build up in
the cooling system. To prevent scalding or
injury, do not remove the pressure cap
while the system is hot or under pressure.
Do not use a pressure cap other than the
one specified for your vehicle. Personal
injury or engine damage may result.
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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.

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392SERVICING AND MAINTENANCE
Air Cleaner Assembly
Inspect air cleaner housing for proper assembly
and fit. Make certain that the air cleaner is
properly positioned and that the cover is tight.
Check all hoses leading to the air cleaner for
tightness. The air filter element must also be
clean and serviced according to the instructions
outlined in the Scheduled Maintenance section
of this manual.
Tampering With Noise Control System
Prohibited

Federal law prohibits the following acts or the
causing thereof: (1) the removal or rendering
inoperative by any person, other than for purposes
of maintenance, repair, or replacement, of any
device or element of design incorporated into any
new vehicle for the purpose of noise control prior to
its sale or delivery to the ultimate purchaser or while
it is in use, or (2) the use of the vehicle after such
device or element of design has been removed or
rendered inoperative by any person.

Among those acts presumed to constitute
tampering are the acts listed below. AIR CLEANER

Removal of the air cleaner.
Removal of the air cleaner filter element from
the air cleaner housing.
Removal of the air ducting.
EXHAUST SYSTEM
Removal or rendering inoperative exhaust
system components including the muffler or
tailpipe.
ENGINE COOLING SYSTEM
Removal or rendering inoperative the fan
clutch.
Removal of the fan shroud.
Noise Emission Warranty
The manufacturer warrants that this vehicle as
manufactured by the manufacturer, was
designed, built and equipped to conform at the
time it left the manufacturer's control with all
applicable U.S. EPA Noise Control Regulations.
This warranty covers this vehicle as designed,
built and equipped by the manufacturer, and is
not limited to any particular part, component or
system of the vehicle manufactured by the
manufacturer. Defects in design, assembly or in
any part, component or system of the vehicle as
manufactured by the manufacturer, which, at
the time it left the manufacturer's control,
caused noise emissions to exceed Federal
standards, are covered by this warranty for the
life of the vehicle.

21_DPF_OM_EN_USC_t.book Page 392

TECHNICAL SPECIFICATIONS439
FLUID CAPACITIES
6.4L GASOLINE ENGINE
6.7L DIESEL ENGINE
US Metric
Fuel (Approximate)
Standard Rear Tank 52 Gallons197 Liters
Optional Midship Tank 22 Gallons83 Liters
Engine Oil With Filter
6.4L Engine 7 Quarts6.6 Liters
Cooling System
6.4L Engine 16.6 Quarts15.7 Liters
USMetric
Fuel (Approximate)
Standard Rear Tank 52 Gallons197 Liters
Optional Midship Tank 22 Gallons83 Liters
Diesel Exhaust Fluid Tank (Approximate) 8.7 Gallons33 Liters
Engine Oil With Filter
6.7L Turbo Diesel Engine 12 Quarts11.4 Liters
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440TECHNICAL SPECIFICATIONS
ENGINE FLUIDS AND LUBRICANTS
6.4L GASOLINE ENGINE
Cooling System
6.7L Engine Chassis Cab 3500/4500 with AS69RC 22.3 Quarts21.1 Liters
6.7L Engine Chassis Cab 5500 with AS69RC 22.8 Quarts21.6 Liters
USMetric
Component Fluid, Lubricant, or Genuine Part
Engine CoolantWe recommend you use Mopar Antifreeze/Coolant 10–Year/150,000 Mile (240,000 km)
Formula OAT (Organic Additive Technology).
Engine Oil – 6.4L Engine For best performance and maximum protection under all types of operating conditions, the
manufacturer only recommends full synthetic engine oils that meet the American Petroleum
Institute (API) categories of SN. The manufacturer recommends the use of Pennzoil Ultra
0W-40 or equivalent Mopar engine oil meeting the requirements of FCA Material Standard
MS-12633 for use in all operating temperatures.
Engine Oil Filter – 6.4L Engine We recommend you use a Mopar Engine Oil Filter. If a Mopar Engine Oil Filter is unavailable
only use filters that meet or exceed SAE/USCAR-36 Filter Performance Requirements.
Fuel Selection – 6.4L Engine 87 Octane (R+M)/2 Method, 0-15% Ethanol (Do not use E-85).

21_DPF_OM_EN_USC_t.book Page 440

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)
9

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