2021 RAM CHASSIS CAB Owners Manual

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.
8

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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.

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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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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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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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388SERVICING AND MAINTENANCE
Fluid Level Check — Eight-Speed
Transmission
The fluid level is preset at the factory and does
not require adjustment under normal operating
conditions. Routine fluid level checks are not
required, therefore the transmission has no
dipstick. An authorized dealer can check your
transmission fluid level using special service
tools.
If you notice fluid leakage or transmission
malfunction, visit an authorized dealer
immediately to have the transmission fluid
level checked. Operating the vehicle with
an improper fluid level can cause severe
transmission damage.
Fluid Level Check — Six-Speed
Transmission
It is best to check the fluid level when the
transmission is at normal operating
temperature (158-176°F / 70-80°C). This
normally occurs after at least 15 miles (25 km)
of driving. At normal operating temperature the
fluid cannot be held comfortably between the
fingertips. You can read the transmission sump
temperature in the instrument cluster screen
Ú page 90. Use the following procedure to check the
transmission fluid level properly:

1. Monitor the transmission temperature
using the instrument cluster display, and
operate the vehicle as required to reach
the normal operating temperature. If the
transmission is not functioning properly, or
the vehicle cannot be driven, see the NOTE
and CAUTION below about checking the
fluid level at colder temperatures.

2. Park the vehicle on level ground.
3. Run the engine at normal idle speed for at least 60 seconds, and leave the engine
running for the rest of this procedure.
4. Fully apply the parking brake, and press the brake pedal.
5. Place the gear selector momentarily into each gear position (allowing time for the
transmission to fully engage in each
position), ending with the transmission in
PARK.
6. Remove the dipstick, wipe it clean and reinsert it until seated.
CAUTION!
Do not use chemical flushes in your
transmission as the chemicals can damage
your transmission components. Such damage
is not covered by the New Vehicle Limited
Warranty.
CAUTION!

If a transmission fluid leak occurs, visit an
authorized dealer immediately. Severe
transmission damage may occur. An authorized
dealer has the proper tools to adjust the fluid
level accurately.

21_DPF_OM_EN_USC_t.book Page 388

SERVICING AND MAINTENANCE389
7. Remove the dipstick again and note the
fluid level on both sides. The fluid level
reading is only valid if there is a solid
coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full
of fluid if the actual level is at or above the
hole. The fluid level should be between the
“HOT” (upper) reference holes on the
dipstick at normal operating temperature.
If the fluid level is low, add fluid through the
dipstick tube to bring it to the proper level.
Do not overfill. Use ONLY the specified fluid
Ú page 444. After adding any quantity of oil
through the dipstick tube, wait a minimum
of two minutes for the oil to fully drain into
the transmission before rechecking the
fluid level.
NOTE:

If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two “COLD” (lower) holes on the
dipstick with the fluid at 60-70°F / 16-21°C. Only
use the COLD region of the dipstick as a rough refer -
ence when setting the fluid level after a transmis -sion service or fluid change. Re-check the fluid level,
and adjust as required, once the transmission
reaches normal operating temperature.

8. Reinsert the dipstick. Check for leaks.
Release the parking brake.
NOTE:

If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two COLD (lower) holes on the dipstick
with the fluid at 68-86°F / 20-30°C. Only use the
COLD region of the dipstick as a rough reference
when setting the fluid level after a transmission
service or fluid change. Re-check the fluid level, and
adjust as required, once the transmission reaches
normal operating temperature.

Fluid And Filter Changes — Eight-Speed
Transmission
Under normal operating conditions, the fluid
installed at the factory will provide satisfactory
lubrication for the life of the vehicle.

Routine fluid and filter changes are not required.
However, change the fluid and filter if the fluid
becomes contaminated (with water, etc.), or if the
transmission is disassembled for any reason.

Fluid And Filter Changes — Six Speed
Transmission
For the proper maintenance intervals
Ú page 354.
In addition, change the fluid and filters if the
fluid becomes contaminated (with water, etc.),
or if the transmission is disassembled for any
reason.
CAUTION!
If the fluid temperature is below 50°F (10°C)
it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough
to produce an accurate reading. Run the
engine at idle, in PARK, to warm the fluid.
CAUTION!
If the fluid temperature is below 50°F (10°C)
it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough
to produce an accurate reading. Run the
engine at idle, in PARK, to warm the fluid.
8

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390SERVICING AND MAINTENANCE
Selection Of Lubricant

It is important to use the proper transmission
fluid to ensure optimum transmission
performance and life. Use only the
manufacturer’s specified transmission fluid

Ú
page 444. It is important to maintain the
transmission fluid at the correct level using the
recommended fluid. No chemical flushes should
be used in any transmission; only the approved
lubricant should be used.

REAR AXLE AND 4X4 FRONT DRIVING
A
XLE FLUID LEVEL
For models with 9.25 in Front Axles and 11.5 in
Rear Axles Ú page 444. For normal service,
periodic fluid level checks are not required.
When the vehicle is serviced for other reasons,
the exterior surfaces of the axle assembly
should be inspected.
When checking the fluid level, the vehicle
should be in a level position. The fluid level at
room temperature should be as follows:
3500 Front Axle: ¼ inch ± ¼ inch (6.4 mm ±
6.4 mm) below the bottom of the fill hole.
3500 Rear Axle: ¼ inch ± ¼ inch (6.4 mm ±
6.4 mm) below the bottom of the fill hole.
4500/5500 Front Axle: ¼ inch +/- ¼ inch
(6.4 mm ± 6.4 mm) below the bottom of the fill
hole.
4500/5500 Rear Axle: 1/8 inch +/- 1/8 inch
(3.2 mm +/- 3.2 mm) below the bottom of the
fill hole.
Drain And Refill
On 4500/5500 vehicles, remove the lower bolt
to drain the axle fluid.

4500/5500 Rear Axle Plugs

For the proper maintenance intervals
Ú page 354.
CAUTION!

Using a transmission fluid other than the
manufacturer’s recommended fluid may cause
deterioration in transmission shift quality and/or
torque converter shudder, and (for six-speed
transmissions) will require more frequent fluid
and filter changes
Ú
page 444.

1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug

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