2023 JEEP GLADIATOR engine

148STARTING AND OPERATING
NOTE:Engine start-up in very low ambient temperature
could result in evident white smoke. This condition
will disappear as the engine warms up.
AUTOMATIC TRANSMISSION
Start the engine with the transmission gear
selector in the PARK (P) position. Apply the brake
before shifting to any driving range.
EXTREME COLD WEATHER
The cartridge block heater clips into the engine
block near the water jacket and transfers heat to
the coolant. It requires a 110–115 Volt AC
electrical outlet with a grounded, three-wire
extension cord. Its use is recommended for
environments that routinely fall below -10°F
(-23°C). It should be used when the vehicle has not
been running overnight or longer periods and
should be plugged in two hours prior to start. Its
use is required for cold starts with temperatures
under -20°F (-28°C).
NOTE:The engine block heater and heater cord are
factory installed options. If your vehicle is not
equipped, engine block heaters and heater cords
are available from an authorized Mopar® dealer.
A 12 Volt heater built into the fuel filter housing
aids in preventing fuel gelling. It is controlled by
a built-in thermostat.
A Diesel Pre-Heat system both improves engine
starting and reduces the amount of white
smoke generated by a warming engine.
NORMAL STARTING
Observe the instrument cluster lights when
starting the engine.
NOTE:Normal starting of either a cold or a warm engine is
obtained without pumping or pressing the accel -
erator pedal.

1. Always apply the parking brake.

2. Press and hold the brake pedal while pushing the ENGINE START/STOP button once.
NOTE:A delay of the start of up to five seconds is possible
under very cold conditions. The “Wait to Start”
telltale will be illuminated during the preheat
process. When the engine “Wait To Start” telltale
turns off the engine will automatically crank.
Do not leave the key fob in or near the vehicle,
or in a location accessible to children, and do
not leave the ignition of a vehicle equipped
with Keyless Enter ‘n Go™ in the ACC or ON/
RUN position. A child could operate power
windows, other controls, or move the vehicle.
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build-up
may cause serious injury or death.
CAUTION!
The engine is allowed to crank as long as
25 seconds. If the engine fails to start during
this period, please wait at least two minutes
for the starter to cool before repeating start
procedure.
If the Water in Fuel Indicator Light remains on,
DO NOT START engine before you drain the
water from the fuel filters to avoid engine
damage Ú page 368.
WARNING!
CAUTION!
If the Water in Fuel Indicator Light remains on,
DO NOT START the engine before you drain the
water from the fuel filters to avoid engine
damage Úpage 368.

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STARTING AND OPERATING149
(Continued)
3. The system will automatically engage the
starter to crank the engine. If the vehicle fails
to start, the starter will disengage automat-
ically after 25 seconds.
4. If you wish to stop the cranking of the engine prior to the engine starting, push the ENGINE
START/STOP button again.
5. Check that the Oil Pressure Warning Light has turned off.
6. Release the parking brake.
STARTING FLUIDS
The engine is equipped with a glow plug preheating
system. If the instructions in this manual are
followed, the engine should start in all conditions
and no type of starting fluid should be used.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the diesel engine is
operating:
All message center lights are off.
Malfunction Indicator Light (MIL) is off.
Engine Oil Pressure telltale is not illuminated.
Voltmeter operation.
The voltmeter may show a gauge fluctuation at
various engine temperatures. This is caused by the
glow plug heating system. The number of cycles
and the length of the cycling operation is controlled by the engine control module. Glow plug heater
operation can run for several minutes. Once the
heater operation is complete the voltmeter needle
will stabilize.
COLD WEATHER PRECAUTIONS
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following charts suggest these options:
Fuel Operating Range
NOTE:Use Ultra Low Sulfur Diesel (ULSD) Fuels
ONLY.

Fuel Operating Range Chart

*Number 1 ULSD Fuel should only be used where
extended arctic conditions 0°F (-18°C) exist.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build-up
may cause serious injury or death.
When leaving the vehicle, always make sure
the keyless ignition node is in the OFF posi -
tion, remove the key fob from the vehicle and
lock the vehicle.
Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing chil -
dren to be in a vehicle unattended is
dangerous for a number of reasons. A child or
others could be seriously or fatally injured.
Children should be warned not to touch the
parking brake, brake pedal or the gear
selector.
Do not leave the key fob in or near the vehicle,
or in a location accessible to children, and do
not leave the ignition of a vehicle equipped
with Keyless Enter ‘n Go™ in the ACC or ON/
RUN position. A child could operate power
windows, other controls, or move the vehicle.
WARNING!
4

23_JT_OM_EN_USC_t.book Page 149

150STARTING AND OPERATING
NOTE:
Use of Climatized ULSD Fuel or Number 1 ULSD
fuel results in a noticeable decrease in fuel
economy.
Climatized ULSD fuel is a blend of Number 2
ULSD fuel and Number 1 ULSD fuel which
reduces the temperature at which wax crystals
form in fuel.
The fuel grade should be clearly marked on the
pump at the fuel station.
The engine requires the use of Ultra Low Sulfur
Diesel Fuel . Use of incorrect fuel could result in
engine and exhaust system damage
Ú page 421.
If climatized or Number 1 ULSD fuel is not avail -
able, and you are operating below 20°F (-6°C),
in sustained arctic conditions, Mopar®
Premium Diesel Fuel Treatment (or equivalent) is recommended to avoid gelling (see Fuel Oper
-
ating Range Chart).
Engine Oil Usage
See Engine Fluids and Lubricants for the correct
engine oil viscosity Ú page 424.
Engine Warm-Up
Avoid full throttle operation when the engine is
cold. When starting a cold engine, bring the engine
up to operating speed slowly to allow the oil
pressure to stabilize as the engine warms up.
If temperatures are below 32°F (0°C), operate the
engine at moderate speeds for five minutes before
full loads are applied.
ENGINE IDLING
Avoid prolonged idling. Long periods of idling may
be harmful to your engine because combustion chamber temperatures can drop so low that the
fuel may not burn completely. Incomplete
combustion allows carbon and varnish to form on
piston rings, cylinder head valves, turbocharger,
and injector nozzles. Also, the unburned fuel can
enter the crankcase, diluting the oil and causing
rapid wear to the engine.
STOPPING THE ENGINE
After full load operation, idle the engine for a few
minutes before shutting it down. This idle period
will allow the lubricating oil and coolant to carry
excess heat away from the turbocharger.
NOTE:Refer to the following chart for proper engine
shutdown.
Driving Condition Load Turbocharger Temperature Idle Time (min.) Before Engine
Shutdown
Stop and Go EmptyCoolNone
Stop and Go Medium 0.5
Highway Speeds MediumWarm 1.0
City Traffic Maximum GCWR 1.5
Highway Speeds Maximum GCWR 2.0
Uphill Grade Maximum GCWR Hot2.5

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STARTING AND OPERATING151
NOTE:Under certain conditions the Stop/Start system
may be temporarily disabled and the engine fan
will run after the engine is turned off to protect the
engine. These conditions are under high load and
high temperature conditions.
COOLING SYSTEM TIPS — AUTOMATIC
T
RANSMISSION
To reduce the potential for engine and
transmission overheating in high ambient
temperature conditions, take the following actions:
City Driving — When stopped, shift the transmis -
sion into NEUTRAL (N) and increase engine idle
speed.
Highway Driving — Reduce your speed.
Up Steep Hills — Select a lower transmission
gear.
Air Conditioning — Turn it off temporarily.
NOTE:If the coolant temperature is too high, the A/C will
automatically turn off.
Do Not Operate The Engine With Low Oil
Pressure
If the Low Oil Pressure Warning Light turns on while
driving, stop the vehicle and shut down the engine
as soon as possible. After the vehicle is safely
stopped, restart the engine and monitor the lamp. If the lamp is still illuminated, shut the engine off,
contact an authorized dealer, and do not operate
the vehicle until the cause is corrected. If the lamp
is no longer illuminated, the engine can be
operated, but should be taken to an authorized
dealer as soon as possible for further inspection.
NOTE:Do not operate the vehicle until the cause is
corrected. This light does not show how much oil is
in the engine. The engine oil level must be checked
under the hood.
Do Not Operate The Engine With Failed
Parts
All engine failures give some warning before the
parts fail. Be on the alert for changes in
performance, sounds, and visual evidence that the
engine requires service. Some important clues are:
Engine misfiring or vibrating severely
Sudden loss of power
Unusual engine noises
Fuel, oil or coolant leaks
Sudden change, outside the normal operating
range, in the engine operating temperature
Excessive smoke
Oil pressure drop
ENGINE BREAK-IN RECOMMENDATIONS —
GASOLINE ENGINE (IF EQUIPPED)
A long break-in period is not required for the engine
and drivetrain (transmission and axle) in your
vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles (100 km),
speeds up to 50 or 55 mph (80 or 90 km/h) are
desirable.
While cruising, brief full-throttle acceleration within
the limits of local traffic laws contributes to a good
break-in. Wide-open throttle acceleration in low
gear can be detrimental and should be avoided.
The engine oil installed in the engine at the factory
is a high-quality energy conserving type lubricant.
Oil changes should be consistent with anticipated
climate conditions under which vehicle operations
will occur.
For the recommended viscosity and quality grades
see Ú page 424.
CAUTION!
If oil pressure falls to less than normal readings,
shut the engine off immediately. Failure to do so
could result in immediate and severe engine
damage.
4

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152STARTING AND OPERATING
NOTE:A new engine may consume some oil during its first
few thousand miles (kilometers) of operation. This
should be considered a normal part of the break-in
and not interpreted as a problem.
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE (IF EQUIPPED)
The diesel engine does not require a break-in
period due to its construction. Normal operation is
allowed, providing the following recommendations
are followed:
Warm up the engine before placing it under
load.
Do not operate the engine at idle for prolonged
periods.
Use the appropriate transmission gear to
prevent engine lugging.
Observe vehicle oil pressure and temperature
indicators.
Check the coolant and oil levels frequently.
Vary throttle position at highway speeds when
carrying or towing significant weight.
NOTE:Light duty operation such as light trailer towing or
no load operation will extend the time before the
engine is at full efficiency. Reduced fuel economy
and power may be seen at this time.
The engine oil installed in the engine at the factory
is a high-quality energy conserving type lubricant.
Oil changes should be consistent with anticipated
climate conditions under which vehicle operations
will occur. For recommended viscosity and quality
grades Úpage 424. NON-DETERGENT OR
STRAIGHT MINERAL OILS MUST NEVER BE USED.
PARKING BRAKE
Before exiting the vehicle, make sure that the
parking brake is fully applied. Also, be certain to
leave an automatic transmission in PARK, or
manual transmission in REVERSE or FIRST gear.
The parking brake lever is located in the center
console. To apply the parking brake, pull the lever
up as firmly as possible. To release the parking
brake, pull the lever up slightly, push the center
button, then lower the lever completely.
Parking Brake Lever

When the parking brake is applied with the ignition
switch ON, the Brake Warning Light in the
instrument cluster will illuminate.
NOTE:
When the parking brake is applied and the auto -
matic transmission is placed in gear, the Brake
Warning Light will flash. If vehicle speed is
detected, a chime will sound to alert the driver.
Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application.
CAUTION!
Never use Non-Detergent Oil or Straight Mineral
Oil in the engine or damage may result.

23_JT_OM_EN_USC_t.book Page 152

154STARTING AND OPERATING
NOTE:During cold weather, you may experience
increased effort in shifting until the transmission
fluid warms up. This is normal.

Manual Transmission Shifter
To shift the gears, fully press the clutch pedal and
place the gear selector into the desired gear
position (the diagram for the engagement of the
gears is displayed on the handle of the selector).
The gear position will be displayed in the
instrument cluster.
To engage REVERSE gear from the NEUTRAL
position, lift the REVERSE ring, located below the
knob and move the gear selector all the way left
and then forward.
SHIFTING
Fully press the clutch pedal before shifting gears.
As you release the clutch pedal, lightly press the
accelerator pedal.
You should always use FIRST gear when starting
from a standing position.
NOTE:A certain amount of noise from the transmission is
normal. This noise can be most noticeable when
the vehicle is idling in NEUTRAL with the clutch
engaged (clutch pedal released), but it may also be
heard when driving. The noise may also be more
noticeable when the transmission is warm. This
noise is normal and is not an indication of a
problem with your clutch or transmission.
Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for
both fuel economy and performance, it should be
upshifted as listed in the recommended shift
speed chart. Shift at the vehicle speeds listed for
acceleration. When heavily loaded or pulling a
trailer, these recommended up shift speeds may
not apply.
NOTE:Vehicle speeds shown in the chart above are for 2H and 4H only. Vehicle speeds in 4L would be significantly less.
Manual Transmission Shift Speeds in MPH (KM/H)
Engine
Speeds 1 to 22 to 33 to 44 to 55 to 6
3.6L Accel.
15 (24) 24 (39)50 (80)65 (104) 70 (112)
Cruise 10 (16) 19 (31)40 (64)55 (88)65 (105)

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STARTING AND OPERATING155
(Continued)
(Continued)
DOWNSHIFTING
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving
down steep hills. In addition, downshifting at the
right time provides better acceleration when you
desire to resume speed. Downshift progressively.
Do not skip gears to avoid overspeeding the engine
and clutch.
NOTE:Above certain speeds, downshifts may be blocked
and not available.
Maximum Recommended Downshift
Speeds
NOTE:Vehicle speeds shown in the chart above are for
2H and 4H only, vehicle speeds in 4L would be
significantly less.
AUTOMATIC TRANSMISSION —
IF EQUIPPED
You must press and hold the brake pedal while
shifting out of PARK.
WARNING!
Do not downshift for additional engine braking
on a slippery surface. The drive wheels could
lose their grip, and the vehicle could skid.
CAUTION!
Skipping gears and downshifting into lower
gears at higher vehicle speeds can damage
the engine and clutch systems. Any attempt to
shift into lower gear with clutch pedal pressed
may result in damage to the clutch system.
Shifting into lower gear and releasing the
clutch may result in engine damage.
When descending a hill, be very careful to
downshift one gear at a time to prevent over -
speeding the engine which can cause engine
damage, and/or clutch damage, even if the
clutch pedal is pressed. If transfer case is in
low range the vehicle speeds to cause engine
and clutch damage are significantly lower.
Failure to follow the maximum recommended
downshifting speeds may cause engine
damage and/or damage the clutch, even if the
clutch pedal is pressed.
Descending a hill in low range with clutch
pedal pressed could result in clutch damage.
CAUTION!
Failure to follow the maximum recommended
downshifting speeds may cause the engine to
overspeed and/or damage the clutch disc, even
if the clutch pedal is pressed.
CAUTION!Manual Transmission Downshift Speeds in
MPH (KM/H)

Gear
Selection 6 to 5 5 to 4 4 to 3 3 to 2 2 to 1
Maximum Speed 80
(129) 70
(113) 50
(81) 30
(48) 15
(24)

WARNING!
Never use the PARK position as a substitute
for the parking brake. Always apply the
parking brake fully when exiting the vehicle to
guard against vehicle movement and possible
injury or damage.
4

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156STARTING AND OPERATING
(Continued)
IGNITION PARK INTERLOCK
This vehicle is equipped with an Ignition Park
Interlock system which requires the transmission
to be in PARK before the ignition can be turned to
the OFF position. This helps the driver avoid
inadvertently leaving the vehicle without placing
the transmission in PARK. This system also locks
the transmission in PARK whenever the ignition is
in the OFF position.
NOTE:The transmission is NOT locked in PARK when the
ignition is in the ACC position (even though the
engine will be off). Ensure that the transmission is
in PARK, and the ignition is OFF (not in ACC
position) before exiting the vehicle.
Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the transmission gear selector out of
PARK with the brake pedal released. Make
sure the transmission is in PARK before
exiting the vehicle.
The transmission may not engage PARK if the
vehicle is moving. Always bring the vehicle to a
complete stop before shifting to PARK, and
verify that the transmission gear position indi -
cator solidly indicates PARK (P) without
blinking. Ensure that the vehicle is completely
stopped, and the PARK position is properly
indicated, before exiting the vehicle.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accelerate
quickly forward or in reverse. You could lose
control of the vehicle and hit someone or
something. Only shift into gear when the
engine is idling normally and your foot is firmly
pressing the brake pedal.
WARNING!
Unintended movement of a vehicle could
injure those in or near the vehicle. As with all
vehicles, you should never exit a vehicle while
the engine is running. Before exiting a vehicle,
always come to a complete stop, then apply
the parking brake, shift the transmission into
PARK, and turn the ignition OFF. When the
ignition is in the OFF position, the transmis -
sion is locked in PARK, securing the vehicle
against unwanted movement.
When exiting the vehicle, always make sure
the ignition is in the OFF position, remove the
key fob from the vehicle, and lock the vehicle.
Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing chil -
dren to be in a vehicle unattended is
dangerous for a number of reasons. A child or
others could be seriously or fatally injured.
Children should be warned not to touch the
parking brake, brake pedal or the transmis -
sion gear selector.
Do not leave the key fob in or near the vehicle
(or in a location accessible to children), and do
not leave the ignition in the ACC or ON/RUN
position. A child could operate power
windows, other controls, or move the vehicle.
WARNING!CAUTION!
Shift into or out of PARK or REVERSE only after
the vehicle has come to a complete stop.
Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is above
idle speed.
Before shifting into any gear, make sure your
foot is firmly pressing the brake pedal.

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