2020 Ram 4500 Chassis Cab Service

362SERVICING AND MAINTENANCE
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 (engage -
ment 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 main -
tained 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 under -
side 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 misposi
-
tioned 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.
Under normal operating conditions, the cata-
lytic converter will not require maintenance.
However, it is important to keep the engine
properly tuned to ensure proper catalyst opera-
tion and prevent possible catalyst damage.
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, refer to
“Safety Tips” in “Safety” for further informa -
tion.
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.
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
malfunction, particularly involving engine
misfire or other apparent loss of perfor -
mance, 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.

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SERVICING AND MAINTENANCE363
NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.
In unusual situations involving grossly malfunc -
tioning engine operation, a scorching odor may
suggest severe and abnormal catalyst over -
heating. If this occurs, stop the vehicle, turn off
the engine and allow it to cool. Service,
including a tune-up to manufacturer's specifica-
tions, 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 Engine Coolant Checks
Check the engine coolant (antifreeze) protec-
tion every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant (antifreeze) 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 (if equipped) 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 (if equipped) or the back of the
radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and tight-
ness 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. 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.7

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366SERVICING 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 oper -
ating temperature is satisfactory, the coolant
bottle need only be checked once a month.
When additional engine coolant (antifreeze) is
needed to maintain the proper level, it should
be added to the coolant bottle. Do not overfill.
Points To Remember
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 (antifreeze) addi-
tions are required, the cooling system should
be pressure tested for leaks.
Maintain engine coolant (antifreeze) concen
-
tration at a minimum of 50% OAT coolant
(conforming to MS.90032) and distilled
water for proper corrosion protection of your
engine which contains aluminum compo -
nents.
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 coolant (antifreeze)
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 mani -
fold 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 MAINTENANCE367
(Continued)
Brake System
In order to ensure brake system performance,
all brake system components should be
inspected periodically. Refer to the “Mainte -
nance Plan” in this section for the proper main -
tenance intervals.
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.
Refer to “Fluids And Lubricants” in “Technical
Specifications” for further information.
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. Refer to “Fluids And Lubri
-
cants” in “Technical Specifications” for
further information. Using the wrong type of
brake fluid can severely damage your brake
system and/or impair its performance. The
proper type of brake fluid for your vehicle is
also identified on the original factory
installed hydraulic master cylinder reser -
voir.
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 reser -
voir 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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368SERVICING AND MAINTENANCE
Automatic Transmission
Selection Of Lubricant
It is important to use the proper transmission
fluid to ensure optimum transmission perfor-
mance and life. Use only the manufacturer’s
specified transmission fluid. Refer to “Fluids
And Lubricants” in “Technical Specifications”. 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.
Special Additives
The manufacturer strongly recommends
against using any special additives in the trans -
mission. 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.
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 immedi
-
ately to have the transmission fluid level
checked. Operating the vehicle with an
improper fluid level can cause severe transmis -
sion damage.
Fluid Level Check — Six-Speed Transmission
It is best to check the fluid level when the trans -
mission 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 (refer to “Instru -
ment Cluster Display” in “Getting To Know Your
Instrument Panel” for further information).
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. Refer
to “Fluids And Lubricants” in “Technical
Specifications” for fluid specifications.
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.

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SERVICING AND MAINTENANCE369
Use the following procedure to check the trans -
mission 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 posi -
tion), ending with the transmission in PARK.
6. Remove the dipstick, wipe it clean and rein -
sert it until seated. 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
(refer to "Fluids And Lubricants" in “Tech -
nical Specifications” for fluid specifica -
tions). 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 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.
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.
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.
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370SERVICING AND MAINTENANCE
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
Refer to the “Maintenance Plan” for the proper
maintenance intervals.
In addition, change the fluid and filters if the
fluid becomes contaminated (with water, etc.),
or if the transmission is disassembled for any
reason.
Rear Axle And 4x4 Front Driving Axle Fluid
Level
For models with 9.25 in Front Axles and 11.5 in
Rear Axles, refer to “Fluids And Lubricants” in
“Servicing And Maintenance” for further infor -
mation. 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

Refer to “Scheduled Servicing” in this chapter
for the proper maintenance intervals.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.
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug

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SERVICING AND MAINTENANCE371
Lubricant Selection
Refer to “Fluids And Lubricants” in “Technical
Specifications” for further information.
NOTE:
The presence of water in the gear lubricant will
result in corrosion and possible failure of differ -
ential components. Operation of the vehicle in
water, as may be encountered in some
off-highway types of service, will require
draining and refilling the axle to avoid damage.
Limited-Slip Differentials DO REQUIRE limited
slip oil additive (friction modifiers).
NOTE:
Slight noise and mild shuddering may be
evident while turning a vehicle with limited slip
differential on concrete or dry pavement. These
conditions should be considered normal opera -
tion of the limited slip differential.
Transfer Case
Selection Of Lubricant
Use only the manufacturer's recommended
fluid. Refer to “Fluids And Lubricants” in “Tech -
nical Specifications” for further information.
Fluid Level Check
This fluid level can be checked by removing the
filler plug. The fluid level should be to the
bottom edge of the filler plug hole with the
vehicle in a level position.
Drain And Refill
Refer to the “Maintenance Plan” in this section
for the proper maintenance intervals.
Noise Control System Required
Maintenance & Warranty
All vehicles built over 10,000 lbs. (4,535 kg)
Gross Vehicle Weight Rating and manufactured
for sale and use in the United States are
required to comply with the Federal Govern -
ment's Exterior Noise Regulations. These vehi -
cles can be identified by the Noise Emission
Control Label located in the operator's compart -
ment.
Required Maintenance For Noise Control
Systems
The following maintenance services must be
performed every six months or 7,500 miles
(12,000 km) whichever comes first, to ensure
proper operation of the noise control systems.
In addition, inspection and service should be
performed anytime a malfunction is observed or
suspected. Proper maintenance of the entire
vehicle will help the effectiveness of the noise
control systems.
7

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