2021 RAM CHASSIS CAB warning

372SERVICING AND MAINTENANCE
Refrigerant Recovery And Recycling
R-134a — If Equipped
R-134a Air Conditioning Refrigerant is
a hydrofluorocarbon (HFC) that is an
ozone-friendly substance. The manufacturer
recommends that air conditioning service be
performed by an authorized dealer or other
service facilities using recovery and recycling
equipment.
NOTE:
Use only manufacturer approved A/C system
PAG compressor oil and refrigerants.
Refrigerant Recovery And Recycling
R-1234yf — If Equipped
R-1234yf Air Conditioning Refrigerant is a
hydrofluoroolefin (HFO) that is endorsed
by the Environmental Protection Agency and
is an ozone-friendly substance with a low
global-warming potential. The manufacturer
recommends that air conditioning service be
performed by an authorized dealer using
recovery and recycling equipment.
NOTE:
Use only manufacturer approved A/C system
PAG compressor oil, and refrigerants.
Cabin Air Filter Replacement
For the proper maintenance intervals
Úpage 354.
The cabin air filter is located in the fresh air inlet
behind the glove compartment. Perform the
following procedure to replace the filter:

1. Open the glove compartment and remove all contents.
2. With the glove compartment door open,
remove the glove compartment tension
tether and tether clip by sliding the clip
toward the face of the glove compartment
door. Lift the clip out of glove compartment
door and release into dash panel.

Right Side Of Glove Compartment

WARNING!
Do not remove the cabin air filter while the
vehicle is running, or while the ignition is in
the ACC or ON/RUN mode. With the cabin
air filter removed and the blower operating,
the blower can contact hands and may propel
dirt and debris into your eyes, resulting in
personal injury.
1 — Glove Compartment Door
2 — Glove Compartment Tension Tether

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374SERVICING AND MAINTENANCE

8. Pull the tension tether outward and reinstall the
glove compartment past the travel stops by
pushing in on the glove compartment sides.

Glove Compartment

NOTE:
Ensure the glove compartment door hinges and
glove compartment travel stops are fully
engaged.
9. Reattach the glove compartment tension tether by inserting the tether clip in the
glove compartment and sliding the clip
away from the face of the glove
compartment door.ACCESSORY DRIVE BELT INSPECTION
When inspecting accessory drive belts, small
cracks that run across ribbed surface of belt
from rib to rib, are considered normal. These
are not a reason to replace belt. However,
cracks running along a rib (not across) are not
normal. Any belt with cracks running along a rib
must be replaced. Also have the belt replaced if
it has excessive wear, frayed cords or severe
glazing.
Accessory Belt (Serpentine Belt)

Conditions that would require replacement:
Rib chunking (one or more ribs has sepa -
rated from belt body)
Rib or belt wear
Longitudinal belt cracking (cracks between
two ribs)
Belt slips
“Groove jumping" (belt does not maintain
correct position on pulley)
Belt broken (note: identify and correct
problem before new belt is installed)
Noise (objectionable squeal, squeak, or
rumble is heard or felt while drive belt is in
operation)
1 — Glove Compartment Travel Stop
2 — Glove Compartment Tension Tether
3 — Glove Compartment Door
WARNING!
Do not attempt to inspect an accessory
drive belt with vehicle running.
When working near the radiator cooling fan,
disconnect the fan motor lead. The fan is
temperature controlled and can start at any
time regardless of ignition mode. You could
be injured by the moving fan blades.

You can be badly injured working on or
around a motor vehicle. Only do service work
for which you have the knowledge and the
proper equipment. If you have any doubt
about your ability to perform a service job,
take your vehicle to a competent mechanic.

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378SERVICING AND MAINTENANCE
7. Wipe clean the sealing surfaces of the lid
and housing.
8. Install new o-ring back into ring groove on the filter housing and lubricate with clean
engine oil.
NOTE:
Water In Fuel (WIF) sensor is re-usable. Service
kit comes with new o-ring for filter canister and
WIF sensor.
PRIMING IF THE ENGINE HAS RUN OUT
O
F FUEL

1. Add a substantial amount of fuel to the
tank, approximately 2 to 5 gal (8L to 19L).
2. Three priming cycles must be completed.
Turn ignition to the RUN position and wait
approximately 30 seconds. This will activate
the in tank fuel pump. Turn the ignition
switch to the off position, and leave off for at
least 30 seconds. Repeat this procedure
three times before cranking the engine.
3. Start the engine using the “Normal Starting” procedure Ú page 119.
4. Once the engine starts, allow the engine to idle for a minimum of 30 seconds.
NOTE:
The engine may run rough until the air is forced
from all the fuel lines. NOTE:
A maximum blend of 5% biodiesel, meeting
ASTM specification D-975 may be used with
your Cummins diesel engine. (Chassis Cab
models not configured with B20 capability.)
A maximum blend of 20% biodiesel, meeting
ASTM specification D-7467 may be used with
your Cummins diesel engine. (Pickup models
and Chassis Cab models configured with B20
capability.)
WARNING!
Do not open the high pressure fuel system
with the engine running. Engine operation
causes high fuel pressure. High pressure fuel
spray can cause serious injury or death.
CAUTION!
Do not engage the starter motor for more
than 15 seconds at a time. Allow two minutes
between the cranking intervals.
WARNING!
Do not use alcohol or gasoline as a fuel
blending agent. They can be unstable under
certain conditions and be hazardous or
explosive when mixed with diesel fuel.
CAUTION!
Due to lack of lubricants in alcohol or
gasoline, the use of these fuels can cause
damage to the fuel system.

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SERVICING AND MAINTENANCE379
Use of biodiesel mixture in excess of 20% can
negatively impact the fuel filter's ability to
separate water from the fuel, resulting in
high pressure fuel system corrosion or
damage.
Ethanol blends are not recommended or
approved for use with your Cummins diesel
engine.
In addition, commercially available fuel addi -
tives are not necessary for the proper opera -
tion of your Cummins diesel engine.
INTERVENTION REGENERATION
S
TRATEGY — MESSAGE PROCESS FLOW
The Cummins diesel engine meets all
Environmental Protection Agency (EPA) Heavy
Duty Diesel Engine Emissions Standards,
resulting in one of the lowest emitting diesel
engines ever produced.

To achieve these emissions standards, your
vehicle is equipped with a state-of-the-art engine
and exhaust system. The engine and exhaust
after-treatment system work together to achieve
the EPA Heavy Duty Diesel Engine Emissions
Standards. These systems are seamlessly
integrated into your vehicle and managed by the Cummins Powertrain Control Module (PCM).
The PCM manages engine combustion to allow
the exhaust system’s catalyst to trap and burn
Particulate Matter (PM) pollutants, with no input
or interaction on your part.
If the engine is allowed to idle or the truck is
driven on low engine speed drive cycles for more
than two hours, the system will automatically
enter an emissions operating mode that will
increase the engine idle speed to 900 RPM
(1,050 RPM for Chassis Cab). While in this mode,
which is designed to help maintain the Diesel
Particulate Filter, the engine idle speed will return
to normal when the brake pedal is applied.
A small change in engine tone or a slight change
in engine performance while accelerating may
also be noticeable at speeds below 20 mph
(32 km/h). This operating mode may last for up
to an hour of idle time, or around 20 minutes of
driving time.

Additionally, your vehicle has the ability to alert
you to additional maintenance required on your
truck or engine Ú
page 90.
DIESEL EXHAUST FLUID
Diesel Exhaust Fluid (DEF) sometimes known
simply by the name of its active component,
UREA—is a key component of Selective Catalytic
Reduction (SCR) systems, which help diesel
vehicles meet stringent emission regulations.
DEF is a liquid reducing agent that reacts with
engine exhaust in the presence of a catalyst to
convert smog-forming nitrogen oxides (NOx)
into harmless nitrogen and water vapor
Úpage 440.
You can receive assistance in locating DEF in
the United States by calling 866-RAM-INFO
(866-726-4636). In Canada call
1–800–465–2001 (English) or
1–800–387–9983 (French)
WARNING!
A hot exhaust system can start a fire if you
park over materials that can burn. Such
materials might be grass or leaves coming
into contact with your exhaust system. Do not
park or operate your vehicle in areas where
your exhaust system can contact anything
that can burn.
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382SERVICING AND MAINTENANCE
5. With the wiper blade disengaged, remove
the wiper blade from the wiper arm by
holding the wiper arm with one hand and
separating the wiper blade from the wiper
arm with the other hand (move the wiper
blade down toward the base of the wiper
arm and away from the J hook in the end of
the wiper arm).

Removing Wiper From Wiper Arm

6. Gently lower the wiper arm onto the glass. Installing The Front Wipers

1. Lift the wiper arm off of the glass, until the
wiper arm is in the full up position.

2. Position the wiper blade under the hook on the tip of the wiper arm with the wiper
locking tab open.
3. Insert the receiver bracket on the wiper assembly into the hook on the tip of the arm
through the opening in the wiper blade
under the locking tab.
4. Slide the wiper blade up into the hook on the wiper arm until it is latched
(engagement will be accompanied by an
audible click). Fold down the latch release
tab and snap it into its locked position.
5. Gently lower the wiper blade onto the glass.
EXHAUST SYSTEM
The best protection against carbon monoxide
entry into the vehicle body is a properly
maintained engine exhaust system.
If you notice a change in the sound of the exhaust
system; or if the exhaust fumes can be detected
inside the vehicle; or when the underside or rear
of the vehicle is damaged; have an authorized
technician 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 addition, have the exhaust
system inspected each time the vehicle is raised
for lubrication or oil change. Replace as required.

1 — Wiper
2 — Locking Tab
3 — Wiper Arm J Hook
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 Ú
page 333.
A hot exhaust system can start a fire if you
park over materials that can burn. Such
materials might be grass or leaves coming
into contact with your exhaust system.
Do not park or operate your vehicle in areas
where your exhaust system can contact
anything that can burn.

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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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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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SERVICING AND MAINTENANCE387
(Continued)
BRAKE SYSTEM
In order to ensure brake system performance,
all brake system components should be
inspected periodically Ú page 354.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should be
checked when performing under the hood
service or immediately if the brake system
warning lamp indicates system failure.

If necessary, add fluid to bring level within the
designated marks on the side of the reservoir of the
brake master cylinder. Be sure to clean the top of
the master cylinder area before removing cap.
With disc brakes the fluid level can be expected
to fall as the brake linings wear. However, an
unexpected drop in fluid level may be caused by
a leak and a system check should be conducted.

For further information Ú
page 444.
AUTOMATIC TRANSMISSION
Special Additives

The manufacturer strongly recommends against
using any special additives in the transmission.
Automatic Transmission Fluid (ATF) is an
engineered product and its performance may be
impaired by supplemental additives. Therefore,
do not add any fluid additives to the transmission.
The only exception to this policy is the use of special
dyes for diagnosing fluid leaks in six-speed
transmissions. Avoid using transmission sealers as
they may adversely affect seals.

WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your foot
resting or riding on the brake pedal can result
in abnormally high brake temperatures,
excessive lining wear, and possible brake
damage. You would not have your full braking
capacity in an emergency.WARNING!
Use only manufacturer's recommended
brake fluid Úpage 444. Using the wrong
type of brake fluid can severely damage
your brake system and/or impair its perfor -
mance. The proper type of brake fluid for
your vehicle is also identified on the original
factory installed hydraulic master cylinder
reservoir.

To avoid contamination from foreign matter
or moisture, use only new brake fluid or fluid
that has been in a tightly closed container.
Keep the master cylinder reservoir cap
secured at all times. Brake fluid in a open
container absorbs moisture from the air
resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or
prolonged braking, resulting in sudden brake
failure. This could result in a collision.

Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts, causing the brake fluid to catch fire.
Brake fluid can also damage painted and
vinyl surfaces, care should be taken to
avoid its contact with these surfaces.
Do not allow petroleum based fluid to
contaminate the brake fluid. Brake seal
components could be damaged, causing
partial or complete brake failure. This could
result in a collision.
WARNING! (Continued)
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