2023 JEEP GLADIATOR warning

364SERVICING AND MAINTENANCE
(Continued)
CHECKING OIL LEVEL
To ensure proper engine lubrication, the engine oil
must be maintained at the correct level. Check the
oil level at regular intervals, such as every fuel
stop. The best time to check the engine oil level is
about five minutes after a fully warmed up engine
is shut off.
Checking the oil while the vehicle is on level ground
will improve the accuracy of the oil level readings.
There are four possible dipstick types:
Crosshatched zone.
Crosshatched zone marked SAFE.
Crosshatched zone marked with MIN at the low
end of the range and MAX at the high end of the
range.
Crosshatched zone marked with dimples at the
MIN and the MAX ends of the range.
NOTE:Always maintain the oil level within the crosshatch
markings on the dipstick.
Adding 1 qt (1 L) of oil when the reading is at the
low end of the dipstick range will raise the oil level
to the high end of the range marking.
ADDING WASHER FLUID
The fluid reservoir is located in the engine
compartment. Be sure to check the fluid level at
regular intervals. Fill the reservoir with windshield
washer solvent only (not radiator antifreeze). When
refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel and
wipe clean the wiper blades; this will help blade
performance.
To prevent freeze-up of your windshield washer
system in cold weather, select a solution or mixture
that meets or exceeds the temperature range of
your climate. This rating information can be found
on most washer fluid containers.
MAINTENANCE-FREE BATTERY
Your vehicle is equipped with a maintenance-free
battery. You will never have to add water, and
periodic maintenance is not required.
CAUTION!
Overfilling or underfilling the crankcase will
cause aeration or loss of oil pressure. This could
damage your engine.
WARNING!
Commercial windshield washer solvents are
flammable. They could ignite and burn you. Care
must be exercised when filling or working around
the washer solution.
WARNING!
Battery fluid is a corrosive acid solution and
can burn or even blind you. Do not allow
battery fluid to contact your eyes, skin, or
clothing. Do not lean over a battery when
attaching clamps. If acid splashes in eyes or
on skin, flush the area immediately with large
amounts of water Úpage 343.
Battery gas is flammable and explosive. Keep
flame or sparks away from the battery. Do not
use a booster battery or any other booster
source with an output greater than 12 Volts.
Do not allow cable clamps to touch each
other.
Battery posts, terminals, and related accesso -
ries contain lead and lead compounds. Wash
hands after handling.

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SERVICING AND MAINTENANCE365
(Continued)
PRESSURE WASHING
Cleaning the engine compartment with a high
pressure washer is not recommended.
VEHICLE MAINTENANCE
An authorized dealer has the qualified service
personnel, special tools, and equipment to
perform all service operations in an expert
manner. Service Manuals are available which
include detailed service information for your
vehicle. Refer to these Service Manuals before
attempting any procedure yourself.
NOTE:Intentional tampering with emissions control
systems may void your warranty and could result in
civil penalties being assessed against you.
ENGINE OIL
Engine Oil Selection
For the proper engine oil selection Ú page 424.
Vehicles with the Stop/Start system will be
equipped with two batteries. Both the main
and the supplemental batteries must be
disconnected to completely de-energize the
12 Volt electrical system.
Serious injury or death could result if you do
not disconnect both batteries. To learn how to
properly disconnect, see an authorized dealer.
CAUTION!
It is essential when replacing the cables on
the battery that the positive cable is attached
to the positive post and the negative cable is
attached to the negative post. Battery posts
are marked positive (+) and negative (-) and
are identified on the battery case. Cable
clamps should be tight on the terminal posts
and free of corrosion.
If a “fast charger” is used while the battery is
in the vehicle, disconnect both vehicle battery
cables before connecting the charger to the
battery. Do not use a “fast charger” to provide
starting voltage.
WARNING!
Vehicles with the Stop/Start system will be
equipped with two batteries. Both the main
and the supplemental batteries must be
disconnected to completely de-energize the
12 Volt electrical system.
If the negative battery cables are not isolated
properly it can cause a potential power spike
or surge in the system, resulting in damage to
essential electrical components.
CAUTION!
Precautions have been taken to safeguard all
parts and connections however, the pressures
generated by these machines is such that
complete protection against water ingress
cannot be guaranteed.
CAUTION!
WARNING!
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.
8

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366SERVICING AND MAINTENANCE
American Petroleum Institute (API)
Approved Engine Oil
These symbols mean that the oil has been certified
by the API. The manufacturer only recommends API
trademark oils.
The API Starburst trademark certifies
0W-20, 0W-30 and 5W-30 engine oils.
The API Donut trademark certifies 0W-40
and 5W-40 engine oil.
Synthetic Engine Oils
Your engine was designed for synthetic engine oils,
only use synthetic API approved engine oils.
Synthetic engine oils which do not have both the
correct API trademark and the correct SAE viscosity
grade numbers should not be used.
Materials Added To Engine Oil
The manufacturer strongly recommends against
the addition of any additives (other than leak
detection dyes) to the engine oil. Engine oil is an
engineered product and its performance may be
impaired by supplemental additives.
Disposing Of Used Engine Oil And Oil
Filters
Care should be taken in disposing of used engine
oil and oil filters from your vehicle. Used oil and oil
filters, indiscriminately discarded, can present a
problem to the environment. Contact an
authorized dealer, service station, or governmental
agency for advice on how and where used oil and
oil filters can be safely discarded in your area.
ENGINE OIL FILTER
The engine oil filter should be replaced with a new
filter at every engine oil change.
Engine Oil Filter Selection
A full-flow type disposable oil filter should be used
for replacement. The quality of replacement filter
varies considerably. We recommend using a
Mopar® engine oil filter, if a Mopar® engine oil
filter is unavailable only use filters that meet or
exceed SAE/USCAR-36 Filter performance
requirements.
ENGINE AIR CLEANER FILTER
For the proper maintenance intervals see
Úpage 354 for gas engines or Ú page 358 for
diesel engines.
NOTE:Be sure to follow the “Severe Duty Conditions”
maintenance interval if applicable.
CAUTION!
Do not use chemical flushes in your engine oil as
the chemicals can damage your engine. Such
damage is not covered by the New Vehicle
Limited Warranty.
WARNING!
The air induction system (air cleaner, hoses,
etc.) can provide a measure of protection in the
case of engine backfire. Do not remove the air
induction system (air cleaner, hoses, etc.) unless
such removal is necessary for repair or mainte -
nance. Make sure that no one is near the engine
compartment before starting the vehicle with
the air induction system (air cleaner, hoses, etc.)
removed. Failure to do so can result in serious
personal injury.
CAUTION!
All air entering the engine intake must be
filtered. The abrasive particles in unfiltered air
will cause rapid wear to engine components.
Many aftermarket performance air filter
elements do not adequately filter the air
entering the engine. Use of such filters can
severely damage your engine.

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370SERVICING AND MAINTENANCE
5. Close the water drain valve.

Fuel Filter Assembly

6. Wipe clean the underside of the filter housing to prevent contamination from entering fuel
system during service.
7. Remove the fuel filter cap and filter from the housing using a socket. Rotate counter -
clockwise for removal.
Fuel Filter Assembly

8. Remove the used fuel filter cartridge from the cap and dispose of according to your local
regulations.
9. Wipe clean the sealing surfaces of the cap and housing. 10. Lubricate o-ring on the cap with clean engine
oil.
11. Install the new fuel filter cartridge onto the cap.
12. Insert the cap and filter into the housing with clockwise rotation, use a socket to tighten.
13. After engine start, verify the fuel filter cap does not leak.
PRIMING IF THE ENGINE HAS RUN OUT
O
F FUEL — DIESEL ENGINE

1. Add a substantial amount of fuel to the tank,
approximately 2 to 5 gal (8L to 19L).

2. Push ignition switch twice without your foot on brake to put vehicle in RUN position. This will
activate the in tank fuel pump for approxi -
mately 30 seconds. Repeat this process twice.
1 — Water Drain Valve
1 — Fuel Filter Cap
2 — Socket Adapter
CAUTION!
Take care when handling the new fuel filter to
prevent contamination from entering the fuel
system.
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.

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SERVICING AND MAINTENANCE371
3. Start the engine using the Normal Starting procedure Ú page 148.
NOTE:The engine may run rough until the air is forced
from all the fuel lines.
NOTE:
Use of biodiesel mixture in excess of 20% can
negatively impact the fuel filter's ability to sepa -
rate water from the fuel, resulting in high pres -
sure fuel system corrosion or damage.
In addition, commercially available fuel addi -
tives are not necessary for the proper operation
of your diesel engine.
For extreme cold conditions, "Mopar® Premium
Diesel Fuel Treatment" is recommended to
assist with cold starting.
INTERVENTION REGENERATION
S
TRATEGY — MESSAGE PROCESS FLOW
This engine meets all required diesel engine
emissions standards. To achieve these emissions
standards, your vehicle is equipped with a
state-of-the-art engine and exhaust system. These
systems are seamlessly integrated into your
vehicle and managed by the 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. Additionally, your vehicle has the ability to alert you
to additional maintenance required on your vehicle
or engine Ú
page 121.
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.
For further information Ú page 424.
CAUTION!
The starter motor will engage for approximately
30 seconds at a time. Allow two minutes
between 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.
WARNING!
A hot exhaust system can start a fire if you park
over materials that can burn, such as grass or
leaves, and those items that come into contact
with your exhaust system. Do not park or oper -
ate your vehicle in areas where your exhaust sys -
tem can contact anything that can burn.
8

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372SERVICING AND MAINTENANCE
(Continued)
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. This is not a
reason to replace the belt. However, cracks
running along a rib (not across) are not normal. Any
belt with cracks running along a rib must be
replaced. In addition, 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 separated
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
Noise (objectionable squeal, squeak, or rumble
is heard or felt while drive belt is in operation)
NOTE:Identify and correct problem before new belt is
installed.
Some conditions can be caused by a faulty
component such as a belt pulley. Belt pulleys
should be carefully inspected for damage and
proper alignment.
Belt replacement on some models requires the
use of special tools, we recommend having your
vehicle serviced at an authorized dealer.
AIR CONDITIONER MAINTENANCE
For best possible performance, your air conditioner
should be checked and serviced by an authorized
dealer at the start of each warm season. This
service should include cleaning of the condenser
fins and a performance test. Drive belt tension
should also be checked at this time.
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 equip -
ment. If you have any doubt about your ability
to perform a service job, take your vehicle to a
competent mechanic.
WARNING!
Use only refrigerants and compressor lubri -
cants approved by the manufacturer for your
air conditioning system. Some unapproved
refrigerants are flammable and can explode,
injuring you. Other unapproved refrigerants or
lubricants can cause the system to fail,
requiring costly repairs. Refer to Warranty
Information Book, located online, for further
warranty information.

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SERVICING AND MAINTENANCE373
Refrigerant Recovery And Recycling
R-1234yf
R-1234yf Air Conditioning Refrigerant is a Hydroflu -
oroolefin (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
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. Push up on the glove compartment travel stop and lower the door.
Glove Compartment Travel Stop

3. Pivot the glove compartment downward.
4. Disengage the two retaining tabs that secure the cabin air filter access door to the HVAC
housing.

Cabin Air Filter Access Door Retaining Tabs

The air conditioning system contains refrig -
erant under high pressure. To avoid risk of
personal injury or damage to the system,
adding refrigerant or any repair requiring lines
to be disconnected should be done by an
experienced technician.
CAUTION!
Do not use chemical flushes in your air condi -
tioning system as the chemicals can damage
your air conditioning components. Such damage
is not covered by the New Vehicle Limited War -
ranty.
WARNING!
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.
8

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376SERVICING AND MAINTENANCE
(Continued)
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. 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 transmis
-
sion 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 compo -
nents disconnected or removed, such as when
diagnostic testing, or for prolonged periods
during very rough idle or malfunctioning oper -
ating conditions.
WARNING!
Exhaust gases can injure or kill. They contain
Carbon Monoxide (CO), which is colorless and
odorless. Breathing it can make you uncon -
scious and can eventually poison you. To
avoid breathing CO see Ú page 328.
A hot exhaust system can start a fire if you
park over materials that can burn, such as
grass or leaves, and those items that come
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, may seriously
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 performance, have your
vehicle serviced promptly. Continued opera -
tion of your vehicle with a severe malfunction
could cause the converter to overheat,
resulting in possible damage to the converter
and vehicle.
WARNING!

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