service RAM 1500 2023 Owners Manual

352SERVICING AND MAINTENANCE
(Continued)
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 compartment. This is normally a result of
moisture from rain, snow, or high humidity accumulating
on the radiator and being vaporized when the thermostat
opens, allowing hot engine coolant (antifreeze) 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 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 pressure 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 thermostat. Other designs may
result in unsatisfactory engine cooling performance,
poor gas mileage, and increased emissions.
BRAKE SYSTEM
In order to ensure brake system performance, all brake
system components should be inspected periodically
Úpage 334.
Fluid Level Check — Brake Master Cylinder
The fluid level of the brake master cylinder should be
checked whenever the vehicle is serviced, or immediately
if the Brake System Warning Light is on. 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, fluid level can be expected to fall as
the brake pads wear. Brake fluid level should be checked
when pads are replaced. If the brake fluid is abnormally
low, check the system for leaks
Úpage 397.
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 397. 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 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 an 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.

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SERVICING AND MAINTENANCE353
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. Avoid using transmission sealers as they
may adversely affect seals.
Fluid Level Check
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 And Filter Changes
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.
Selection Of Lubricant
It is important to use the proper transmission fluid to
ensure optimum transmission performance and life. Use
only the manufacturer recommended transmission fluid
Úpage 397. 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 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
Úpage 397. This inspection should be made with
the vehicle in a level position.
The fluid level should be even with the bottom of the fill
hole (within 1/4 in (6.4 mm) of edge of hole) for the front
axle and rear axle.

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.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.
WARNING!
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.
CAUTION!
Using a transmission fluid other than the
manufacturer’s recommended fluid may cause
deterioration in transmission shift quality and/or torque
converter shudder
Úpage 397.
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354SERVICING AND MAINTENANCE
Drain And Refill
For the proper maintenance intervals Úpage 334.
Lubricant Selection
For further information Úpage 397.
NOTE:The presence of water in the gear lubricant will result in
corrosion and possible failure of differential 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
Rear axles equipped with a Limited Slip Differential
require that 5 oz. (148 ml) Mopar® Limited Slip Additive
be added to the gear lubricant
Úpage 397. The Mopar®
Limited Slip Additive should be added to the gear lubricant
whenever a fluid change is made to an axle equipped with
a Limited Slip Differential.
NOTE:When refilling a limited slip differential axle which requires
a friction modification additive, the additive should be
added before the gear lubricant to ensure proper
additive fill.
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 (or within 1/8 inch of the bottom) with the
vehicle in a level position.
Drain And Refill
For the proper maintenance intervals Úpage 334.
Selection Of Lubricant
Use only the manufacturer recommended fluid Úpage 397.
FUSES
General Information
WARNING!
 When replacing a blown fuse, always use an appro -
priate 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 indicated 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 material. 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.

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368SERVICING AND MAINTENANCE
Side Marker Lamp
See the following steps to replace:

1. Open the hood.

2. Disconnect and isolate the negative battery cable.
3. Locate the side marker lamp, which can be found on
the back side of the headlamps.

Side Marker Lamp

4. Disengage the side marker socket by rotating counterclockwise a quarter turn.
5. Pull the socket and bulb straight out from the housing.
6. Separate the bulb from the socket without twisting.
7. Reverse the procedure for installation of new bulb and covers.
FOG LAMPS — IF EQUIPPED
Please see an authorized dealer for service on LED and
Halogen front fog lamps.
Halogen
See the following steps to replace:

1. Reach under and behind the front fascia/bumper to access the back of the front fog lamp housing.

2. Disconnect the fog lamp wiring harness connector from the fog lamp bulb.

Fog Lamp Bulb

3. Rotate the bulb counterclockwise a quarter turn to unlock the bulb from the housing.
4. Pull the bulb straight out from the housing.
5. Reverse the procedure to install the bulb and cover.
REAR TAIL/STOP, TURN SIGNAL AND BACKUP
LAMPS

1. Remove the two screws and pushpin retainers that pass through the bed sheet metal.

Tail Lamp Locations

CAUTION!
Do not contaminate the bulb glass by touching it with
your fingers or by allowing it to contact other oily
surfaces. Shortened bulb life will result.
1 — Tail Lamp
2 — Fasteners
3 — Pushpin Retainers

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370SERVICING AND MAINTENANCE
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 European
design standards. Tires designed to this standard have
the tire size molded into the sidewall 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 temporary
emergency use only. Temporary high pressure 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 stan -
dards 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 MAINTENANCE371
TIRE SIZING CHART
EXAMPLE:
Example Size Designation: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M, 31x10.5 R15 LT
P = Passenger car tire size based on US design standards, or
"....blank...." = Passenger car tire based on European design standards, or
LT = Light truck tire based on US design standards, or
T or S = Temporary spare tire or
31 = Overall diameter in inches (in)
215, 235, 145 = Section width in millimeters (mm)
65, 85, 80 = Aspect ratio in percent (%)
 Ratio of section height to section width of tire, or
10.5 = Section width in inches (in)
R = Construction code
 "R" means radial construction, or
 "D" means diagonal or bias construction
15, 16, 18 = Rim diameter in inches (in)
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)
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378SERVICING AND MAINTENANCE
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.
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 in a Run Flat mode
14 psi (96 kPa) condition, please replace the TPMS sensor
as it is not designed to be reused.
NOTE:The 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.
For more information
Úpage 277.
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 MAINTENANCE379
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.
For further information
Úpage 329.
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.
For further information
Úpage 380.
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 pressures
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
NOTE:Wheel Valve Stem must be replaced as well when
installing new tires due to wear and tear in existing tires.
Keep dismounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease, and gasoline.
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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SERVICING AND MAINTENANCE381
Snow Tires
Some areas of the country require the use of snow tires
during the Winter. Snow tires can be identified by a
“mountain/snowflake” symbol on the tire sidewall.
If you need snow tires, select tires equivalent in
size and type to the original equipment tires.
Use snow tires only in sets of four; failure to do
so may adversely affect the safety and handling
of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should not
be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer
to original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.
While studded tires improve performance on ice, skid and
traction capability on wet or dry surfaces may be poorer
than that of non-studded tires. Some states prohibit
studded tires; therefore, local laws should be checked
before using these tire types.
SPARE TIRES — IF EQUIPPED
NOTE:For vehicles equipped with Tire Service Kit instead of a
spare tire, please refer to “Tire Service Kit” in “In Case Of
Emergency” for further information.
For restrictions when towing with a spare tire designated
for temporary emergency use
Úpage 179.
Spare Tire Matching Original Equipped Tire
And Wheel — If Equipped
Your vehicle may be equipped with a spare tire and wheel
equivalent in look and function to the original equipment
tire and wheel found on the front or rear axle of your
vehicle. This spare tire may be used in the tire rotation for
your vehicle. If your vehicle has this option, refer to an
authorized tire dealer for the recommended tire rotation
pattern.
Compact Spare Tire — If Equipped
The compact spare is for temporary emergency use only.
You can identify if your vehicle is equipped with a compact
spare by looking at the spare tire description on the Tire
And Loading Information Placard located on the driver’s
side door opening or on the sidewall of the tire. Compact
spare tire descriptions begin with the letter “T” or “S”
preceding the size designation. Example: T145/80D18
103M.
T, S = Temporary Spare Tire
Since this tire has limited tread life, the original equipment
tire should be repaired (or replaced) and reinstalled on
your vehicle at the first opportunity.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare tire.
Do not install more than one compact spare tire and wheel
on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact or limited use temporary spare installed.
Damage to the vehicle may result.
WARNING!
Compact and collapsible spares are for temporary
emergency use only. With these spares, do not drive
more than 50 mph (80 km/h). Temporary use spares have limited tread life. When the tread is worn to the
tread wear indicators, the temporary use spare tire
needs to be replaced. Be sure to follow the warnings,
which apply to your spare. Failure to do so could result
in spare tire failure and loss of vehicle control.8

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SERVICING AND MAINTENANCE387
The relative performance of tires
depends upon the actual conditions of
their use, however, and may depart
significantly from the norm due to
variations in driving habits, service
practices, and differences in road
characteristics and climate.
TRACTION GRADES
The Traction grades, from highest to
lowest, are AA, A, B, and C. These grades
represent the tire's ability to stop on wet
pavement, as measured under
controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have poor
traction performance.
TEMPERATURE GRADES
The Temperature grades are A (the
highest), B, and C, representing the tire's
resistance to the generation of heat and
its ability to dissipate heat, when tested
under controlled conditions on a
specified indoor laboratory test wheel.
Sustained high temperature can cause
the material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden tire
failure. The grade C corresponds to a
level of performance, which all
passenger vehicle tires must meet
under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel, than the
minimum required by law.
STORING THE VEHICLE
If you are storing your vehicle for more than three weeks,
we recommend that you take the following steps to
minimize the drain on your vehicle's battery:
Disconnect the negative cable from battery.
 Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air condi -
tioning system at idle for about five minutes in the
fresh air and high blower setting. This will ensure
adequate system lubrication to minimize the
possibility of compressor damage when the system
is started again.
WARNING!
The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not
include acceleration, cornering, hydroplaning, or peak
traction characteristics.
WARNING!
The temperature grade for this tire is established for a
tire that is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading,
either separately or in combination, can cause heat
buildup and possible tire failure.
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