2023 RAM CHASSIS CAB service

374SERVICING AND MAINTENANCE
REAR AXLE AND 4X4 FRONT DRIVING
A
XLE FLUID LEVEL
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. If gear oil leakage is
suspected, inspect the fluid level with the vehicle
in a level position.
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 Úpage 344.
Lubricant Selection
For further information Ú page 421.
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 operation of the
limited slip differential.
TRANSFER CASE
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
For the proper maintenance intervals Úpage 344.
Selection Of Lubricant
Use only the manufacturer's recommended fluid
Úpage 421.
NOISE CONTROL SYSTEM REQUIRED
M
AINTENANCE & WARRANTY
All vehicles built over 10,000 lb (4,535 kg) Gross
Vehicle Weight Rating and manufactured for sale
and use in the United States are required to
comply with the Federal Government's Exterior
Noise Regulations. These vehicles can be
identified by the Noise Emission Control Label
located in the operator's compartment.
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug

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SERVICING AND MAINTENANCE375
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.
Exhaust System
Inspect the entire exhaust system for leaks and
damaged parts. Devices such as hangers, clamps,
and U-bolts should be tight and in good condition.
Damaged components, burned or blown out
mufflers, burned or rusted out exhaust pipes
should be replaced according to the procedures
and specifications outlined in the appropriate
service manual. 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 following:
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 of, or rendering inoperative exhaust
system components including the muffler or tail -
pipe.
ENGINE COOLING SYSTEM
Removal of, 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 US 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.
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376SERVICING AND MAINTENANCE
Maintenance Log and Service Chart (Diesel Engines)
Noise Systems Maintenance Chart and Service Log — Insert Month, Day, Year under column mileage closest to the mileage at which service was performed.
MILES
7,500 15,000 22,500 30,000 37,500 45,000 52,500 60,000

KILOMETERS
12,000 24,000 36,000 48,000 60,000 72,000 84,000 96,000

Exhaust system-inspect
Air cleaner assembly-inspect
ODOMETER READING
PERFORMED BY
PERFORMED AT
MILES
67,500 75,000 82,500 90,000 97,500 105,000 112,500 120,000

KILOMETERS
108,000 120,000 132,000 144,000 156,000 168,000 180,000 192,000

Exhaust system-inspect
Air cleaner assembly-inspect
ODOMETER READING
PERFORMED BY
PERFORMED AT

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SERVICING AND MAINTENANCE377
FUSES
General Information
The fuses protect electrical systems against
excessive current.
When a device does not work, you must check the
fuse element inside the blade fuse for a break/
melt.
Also, please be aware that using power outlets for
extended periods of time with the engine off may
result in vehicle battery discharge.

Blade Fuses
Power Distribution Center
The Power Distribution Center is located in the
engine compartment near the battery. This center
contains cartridge fuses, micro fuses, relays, and
circuit breakers. A description of each fuse and
component may be stamped on the inside cover,
otherwise the cavity number of each fuse is
stamped on the inside cover that corresponds to
the following chart.
WARNING!
When replacing a blown fuse, always use an
appropriate replacement fuse with the same
amp rating as the original fuse. Never replace
a fuse with another fuse of higher amp rating.
The use of a fuse with a rating other than indi -
cated may result in a dangerous electrical
system overload. If a properly rated fuse
continues to blow, it indicates a problem in the
circuit that must be corrected. Never replace a
blown fuse with metal wires or any other mate -
rial. Do not place a fuse inside a circuit
breaker cavity or vice versa. Failure to use
proper fuses may result in serious personal
injury, fire and/or property damage.
Before replacing a fuse, make sure that the
ignition is off and that all the other services
are switched off and/or disengaged.
If the replaced fuse blows again, contact an
authorized dealer.
If a general protection fuse for safety systems
(air bag system, braking system), power unit
systems (engine system, transmission
system) or steering system blows, contact an
authorized dealer.
1 — Fuse Element
2 — Blade Fuse with a good/functional fuse
element
3 — Blade fuse with a bad/not functional fuse
element (blown fuse)
CAUTION!
When installing the power distribution center
cover, it is important to ensure the cover is
properly positioned and fully latched. Failure
to do so may allow water to get into the power
distribution center and possibly result in an
electrical system failure.
If it is necessary to wash the engine compart -
ment, take care not to directly hit the fuse box
or the windshield wiper motor with water.
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SERVICING AND MAINTENANCE389

Removing Bulb Socket From Clearance Lamp

3. Pull the bulb straight from it's socket and replace.
TIRES
TIRE SAFETY INFORMATION
Tire safety information will cover aspects of the
following information: Tire Markings, Tire
Identification Numbers, Tire Terminology and
Definitions, Tire Pressures, and Tire Loading.
Tire Markings

Tire Markings

NOTE:
P (Passenger) — Metric tire sizing is based on US
design standards. P-Metric tires have the letter
“P” molded into the sidewall preceding the size
designation. Example: P215/65R15 95H.
European — Metric tire sizing is based on Euro -
pean design standards. Tires designed to this
standard have the tire size molded into the side -
wall beginning with the section width. The letter
"P" is absent from this tire size designation.
Example: 215/65R15 96H.
LT (Light Truck) — Metric tire sizing is based on
US design standards. The size designation for
LT-Metric tires is the same as for P-Metric tires
except for the letters “LT” that are molded into
the sidewall preceding the size designation.
Example: LT235/85R16.
Temporary spare tires are designed for tempo -
rary emergency use only. Temporary high pres -
sure compact spare tires have the letter “T” or
“S” molded into the sidewall preceding the size
designation. Example: T145/80D18 103M.
High flotation tire sizing is based on US design
standards and it begins with the tire diameter
molded into the sidewall. Example: 31x10.5
R15 LT.
1 — US DOT Safety Standards Code
(TIN)
2 — Size Designation
3 — Service Description
4 — Maximum Load
5 — Maximum Pressure
6 — Treadwear, Traction and
Temperature Grades
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SERVICING AND MAINTENANCE391
Service Description:
95 = Load Index
A numerical code associated with the maximum load a tire can carry
H = Speed Symbol
A symbol indicating the range of speeds at which a tire can carry a load corresponding to its load index under certain operating conditions
The maximum speed corresponding to the speed symbol should only be achieved under specified operating conditions (i.e., tire pressure, vehicle loading,
road conditions, and posted speed limits)
Load Identification:
Absence of the following load identification symbols on the sidewall of the tire indicates a Standard Load (SL) tire:
XL = Extra load (or reinforced) tire, or
LL = Light load tire or
C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load – Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure – Maximum pressure indicates the maximum permissible cold tire inflation pressure for this tire
EXAMPLE:
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398SERVICING AND MAINTENANCE
Inflation pressures specified on the placard are
always “cold tire inflation pressure”. Cold tire
inflation pressure is defined as the tire pressure
after the vehicle has not been driven for at least
three hours, or driven less than 1 mile (1.6 km)
after sitting for a minimum of three hours. The cold
tire inflation pressure must not exceed the
maximum inflation pressure molded into the tire
sidewall.
Check tire pressures more often if subject to a
wide range of outdoor temperatures, as tire
pressures vary with temperature changes.
Tire pressures change by approximately 1 psi
(7 kPa) per 12°F (7°C) of air temperature change.
Keep this in mind when checking tire pressure
inside a garage, especially in the Winter.
Example: If garage temperature = 68°F (20°C)
and the outside temperature = 32°F (0°C) then
the cold tire inflation pressure should be increased
by 3 psi (21 kPa), which equals 1 psi (7 kPa) for
every 12°F (7°C) for this outside temperature
condition. Tire pressure may increase from 2 to 6 psi (13 to
40 kPa) during operation. DO NOT reduce this
normal pressure build up or your tire pressure will
be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe
speeds and within posted speed limits. Where
speed limits or conditions are such that the vehicle
can be driven at high speeds, maintaining correct
tire inflation pressure is very important. Increased
tire pressure and reduced vehicle loading may be
required for high-speed vehicle operation. Refer to
an authorized tire dealer or original equipment
vehicle dealer for recommended safe operating
speeds, loading and cold tire inflation pressures.
Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be repaired if
it meets the following criteria:
The tire has not been driven on when flat.
The damage is only on the tread section of your
tire (sidewall damage is not repairable).
The puncture is no greater than ¼ of an inch
(6 mm).
Consult an authorized tire dealer for tire repairs
and additional information.
Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced
immediately with another Run Flat tire of identical
size and service description (Load Index and
Speed Symbol). Replace the tire pressure sensor
as well as it is not designed to be reused.
CAUTION!
After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
WARNING!
High speed driving with your vehicle under
maximum load is dangerous. The added strain
on your tires could cause them to fail. You could
have a serious collision. Do not drive a vehicle
loaded to the maximum capacity at continuous
speeds above 75 mph (120 km/h).
WARNING!
Combining radial ply tires with other types of
tires on your vehicle will cause your vehicle to
handle poorly. The instability could cause a
collision. Always use radial ply tires in sets of
four. Never combine them with other types of
tires.

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SERVICING AND MAINTENANCE399
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive
50 miles (80 km) at 50 mph (80 km/h) after a
rapid loss of inflation pressure. This rapid loss of
inflation is referred to as the Run Flat mode. A Run
Flat mode occurs when the tire inflation pressure is
of/or below 14 psi (96 kPa). Once a Run Flat tire
reaches the Run Flat mode it has limited driving
capabilities and needs to be replaced immediately.
A Run Flat tire is not repairable. When a Run Flat
tire is changed after being driven under a Run Flat
mode 14 psi (96 kPa) condition, please replace the
TPMS sensor as it is not designed to be reused.
NOTE:TPMS sensor must be replaced after driving the
vehicle on a flat tire condition.
It is not recommended driving a vehicle loaded at
full capacity or to tow a trailer while a tire is in the
Run Flat mode.
See the Tire Pressure Monitoring System section
for more information.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions,
do not spin your vehicle's wheels above 30 mph
(48 km/h) or for longer than 30 seconds
continuously without stopping.
Tread Wear Indicators
Tread wear indicators are in the original equipment
tires to help you in determining when your tires
should be replaced.

Tire Tread
These indicators are molded into the bottom of the
tread grooves. They will appear as bands when the
tread depth becomes 1/16 of an inch (1.6 mm).
When the tread is worn to the tread wear
indicators, the tire should be replaced.
Life Of Tire
The service life of a tire is dependent upon varying
factors including, but not limited to:
Driving style.
Tire pressure - Improper cold tire inflation pres
-
sures can cause uneven wear patterns to
develop across the tire tread. These abnormal
wear patterns will reduce tread life, resulting in
the need for earlier tire replacement.
Distance driven.
Performance tires, tires with a speed rating of V
or higher, and Summer tires typically have a
reduced tread life. Rotation of these tires per
the vehicle scheduled maintenance is highly
recommended.
WARNING!
Fast spinning tires can be dangerous. Forces
generated by excessive wheel speeds may
cause tire damage or failure. A tire could
explode and injure someone. Do not spin your
vehicle's wheels faster than 30 mph (48 km/h)
for more than 30 seconds continuously when
you are stuck, and do not let anyone near a
spinning wheel, no matter what the speed.
1 — Tread Wear Indicators
WARNING!
Tires and the spare tire should be replaced after
six years, regardless of the remaining tread.
Failure to follow this warning can result in
sudden tire failure. You could lose control and
have a collision resulting in serious injury or
death.
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