2023 JEEP GLADIATOR engine

SERVICING AND MAINTENANCE363
3.0L DIESEL ENGINE
1 — Battery 6 — Power Distribution Center (Fuses)
2 — Engine Oil Fill 7 — Power Steering Reservoir Cap
3 — Coolant Pressure Reservoir Cap 8 — Engine Oil Dipstick
4 — Brake Fluid Reservoir Cap 9 — Engine Air Cleaner Filter
5 — Washer Fluid Reservoir Cap
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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.
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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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SERVICING AND MAINTENANCE367
Engine Air Cleaner Filter Selection
The quality of replacement engine air cleaner filter
varies considerably. Only high quality Mopar®
filters should be used.
Engine Air Cleaner Filter Inspection and
Replacement — Gasoline Engine
Follow the recommended maintenance intervals
as shown in the Maintenance Schedule in this
section.
Engine Air Cleaner Filter Removal

1. Loosen the fasteners from the engine air cleaner filter cover using a suitable tool.

Engine Air Cleaner Filter Cover
2. Lift the engine air cleaner filer cover to access
the engine air cleaner filter.
3. Remove the engine air cleaner filter from the housing assembly.

Engine Air Cleaner Filter Cover

Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing only if significant
dirt or debris is present before replacing the engine
air cleaner filter.

1. Install the engine air cleaner filter into the housing assembly with the engine air cleaner
filter inspection surface facing downward.

2. Tighten engine air cleaner filter cover fasteners using a suitable tool.
Engine Air Cleaner Filter Inspection and
Replacement — Diesel Engine
Follow the recommended maintenance intervals
as shown in the Maintenance Schedule in this
section.
Engine Air Cleaner Filter Removal

1. Loosen the fasteners from the engine air cleaner filter cover using a suitable tool.

Engine Air Cleaner Filter Cover

1 — Fasteners
2 — Engine Air Cleaner Filter Cover
CAUTION!
Do not overtighten the engine air cleaner filter
cover lid screws or damage may result.
1 — Engine Air Cleaner Filter Cover
2 — Fasteners
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368SERVICING AND MAINTENANCE
2. Lift the engine air cleaner filter cover to access the engine air cleaner filter.
3. Remove the engine air cleaner filter from the housing assembly.

Engine Air Cleaner Filter

Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing only if significant
dirt or debris is present before replacing the engine
air cleaner filter.
1. Install the engine air cleaner filter into the
housing assembly with the engine air cleaner
filter inspection surface facing downward.

2. Tighten engine air cleaner filter cover fasteners using a suitable tool.
DRAINING FUEL/WATER SEPARATOR
F
ILTER — DIESEL ENGINE
The fuel/water separator housing is located inside
the left frame rail in front of the fuel tank. The best
access to this water drain valve is from under the
vehicle. If necessary remove the fuel filter protective cover
to access the water drain valve.

Fuel/Water Separator Filter

If water is detected in the water separator while the
engine is running, or while the ignition switch is in
the ON position, the Water In Fuel Indicator Light
will illuminate and an audible chime will be heard.
At this point you should stop the engine and drain
the water from the filter housing.
1 — Engine Air Cleaner Filter Cover
2 — Engine Air Cleaner Filter
CAUTION!
Do not overtighten the engine air cleaner filter
cover lid screws or damage may result.
CAUTION!
Do not drain the fuel/water separator filter
when the engine is running.
Diesel fuel will damage blacktop paving
surfaces. Drain the filter into an appropriate
container.
1 — Retainers
2 — Fuel Filter Protective Cover

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SERVICING AND MAINTENANCE369

Fuel/Water Separator Filter

Within 10 minutes of vehicle shutdown, turn the
filter drain valve (located on the bottom of the filter
housing) counterclockwise to drain fuel/water;
allow the accumulated water to drain. Leave the
drain valve open until all water and contaminants
have been removed. When clear fuel is visible,
close the drain valve by turning it clockwise.
Upon proper draining of the water from fuel filter
assembly, the Water In Fuel Indicator Light will
remain illuminated for approximately 10 seconds.
If the water was drained while the engine was
running, the Water In Fuel Indicator Light may
remain on for approximately three minutes.
NOTE:Care should be taken in disposing of used fluids
from your vehicle. Used fluids, indiscriminately
discarded, can present a problem to the envi -
ronment. Contact an authorized dealer, service
station, or government agency for advice on recy -
cling programs and for where used fluids and
filters can be properly disposed of in your area.
If more than two ounces or 60 ml of fuel have been
drained, follow the directions for Priming If The
Engine Has Run Out Of Fuel Ú page 370.
FUEL FILTER REPLACEMENT — DIESEL
E
NGINE
NOTE:Using a fuel filter that does not meet FCA US LLC
filtration and water separating requirements can
severely impact fuel system life and reliability.
1. Ensure engine is turned off.

2. Remove the fuel filter protective cover to
access the fuel filter assembly.

Fuel Filter Assembly

3. Place drain pan under the fuel filter assembly.
4. Open the water drain valve, and let any accumulated water and fuel drain.
1 — Water In Fuel Drain Valve
CAUTION!
Diesel fuel will damage blacktop paving
surfaces. Drain the filter into an appropriate
container.
Do not prefill the fuel filter when installing a
new fuel filter. There is a possibility debris
could be introduced into the fuel filter during
this action. It is best to install the filter dry and
allow the in-tank lift pump to prime the fuel
system.
1 — Retainers
2 — Fuel Filter Protective Cover
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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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