engine JEEP WRANGLER UNLIMITED 2021 Owner handbook (in English)

211
Once A Month Or Before A Long Trip
Check the engine oil level about five
minutes after a fully warmed engine is
shut off. Checking the oil level while the
vehicle is on level ground will improve the
accuracy of the oil level reading. Add oil
only when the level is at or below the ADD
or MIN mark.
Check the windshield washer solvent and
add if required.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear.
Inspect the battery and clean and tighten
the terminals as required.
Check the fluid levels of coolant reservoir,
brake master cylinder and power steering
and fill as needed.
Check all lights and other electrical items
for correct operation.At Each Oil Change
Change the engine oil filter.
Inspect the brake hoses and lines.
Inspect the CV/Universal joints.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear, even if it occurs
before the oil indicator system turns on.
Required Maintenance Intervals
Refer to the Maintenance Plan on the
following pages for the required maintenance
intervals.
Maintenance Plan
NOTE:
Once you have carried out the last interven -
tion in the table, continue with the sched -
uled servicing, maintaining the frequency
indicated in the plan by marking each oper -
ation with a dot or dedicated note. Simply
restarting the maintenance from the start of
the plan may cause the allowed interval to be
exceeded for some operations.
CAUTION!
Failure to perform the required
maintenance items may result in damage
to the vehicle.
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SERVICING AND MAINTENANCE
212Mileage or time passed
(whichever comes first)
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 228 240
Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
Change engine oil and
oil filter. * X X X X X X X X X X X X X X X X X X X X
Rotate tires X X X X X X X X X X X X X X X X X X X X
Inspect all door latches
for presence of grease,
reapply if necessary. X X X X X X X X X X X X X X X X X X X X
If using your vehicle for
any of the following:
Dusty or off-road
conditions. Inspect the
engine air cleaner filter,
replace if necessary. X X X X X X X X X X
Inspect the brake
linings, replace if
necessary. X X X X X X X X X X
Inspect exhaust system. XX X XXX
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SERVICING AND MAINTENANCE
214
Inspect the transfer case
fluid.X
X X
Inspect the CV/Universal
joints. X X X X X X X X X X X X X X X X X X X X
Change brake fluid every
24 months if using DOT
4 brake fluid. ** X X X X X X X X X X
Adjust parking brake on
vehicles equipped with
four-wheel disc brakes. X
X X XX
Replace engine air
cleaner filter. X
X X XX
Replace air
conditioning/cabin air
filter. X
X X XXX
Replace spark plugs
(2.0L Engine) *** X
X XX
Replace spark plugs
(3.6L Engine) *** X
X
Mileage or time passed
(whichever comes first)
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 228 240
Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
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215
* See “Severe Duty Conditions” in this
section.
** DOT 4 brake fluid is time based only;
mileage intervals do not apply.*** The spark plug change interval is
mileage based only, yearly intervals do not
apply.
**** This maintenance is recommended by
the manufacturer to the owner, but is not
required to maintain emissions warranty.
Replace accessory drive
belt(s).
X

Flush and replace the
engine coolant at 10
years or 150,000 miles
(240,000 km) whichever
comes first.
X
X

Change transfer case fluid
if using your vehicle for
any of the following:
police, taxi, fleet, or
frequent trailer towing.
X
X
Inspect and replace PCV
valve if necessary. **** X
Mileage or time passed
(whichever comes first)
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 228 240
Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
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SERVICING AND MAINTENANCE
216
Severe Duty Conditions
Change the engine oil and engine oil filter at
every 4,500 miles (7,500 km) or 6 months
if using your vehicle under any of the
following severe duty conditions:
Stop and go driving.
Driving in dusty conditions.
Short trips of less than 10 miles (16 km).
Trailer towing.
Taxi, police, or delivery service (commer-
cial service).
Off-road or desert operation.
Scheduled Servicing — Diesel Engine
Your vehicle is equipped with an automatic
oil change indicator system. The oil change
indicator system will remind you that it is
time to take your vehicle in for engine oil
replacement.
On vehicles equipped with instrument
cluster display, “Oil Change Required” will
be displayed and a single chime will sound,
indicating that an oil change is necessary.
On non-instrument cluster display equipped
vehicles, “Change Oil” will flash in the
instrument cluster odometer and a single
chime will sound, indicating that an oil
change is necessary.

Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures will influence when the
“Oil Change Required” message is displayed. Severe Operating Conditions can cause the
change oil message to illuminate as earlier than
specified. Have your vehicle serviced as soon
as possible, within the next 500 miles
(805 km).

NOTE:
The actual interval for changing engine oil
and replacing the engine oil filter depends
on the vehicle usage conditions, and is
signaled by the warning light or message
in the instrument panel. In any case, it
must never exceed 12,500 miles
(20,000 km) or 1 year
Flush and replace the engine coolant at
120 months or 150,000 miles (240,000 km)
whichever comes first.
The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance trav-
eled. The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use
(dusty areas, severe weather conditions,
very low or very high temperatures for
extended periods, city driving, long periods
of idling). Under no circumstances should
these intervals be exceeded.
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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217
Once A Month Or Before A Long Trip
Check engine oil level.
Check windshield washer fluid level.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear, even if it occurs
before the oil indicator system turns on.

Check the fluid levels of the coolant reservoir
and brake master cylinder, fill as needed.

Check function of all interior and exterior lights.Demanding Vehicle Use
Restore additive level for AdBlue® Diesel
emissions (UREA) (if equipped), when the
lamp is illuminated or the message on the
instrument panel.
Maintenance Plan — Diesel Engine
Required Maintenance Intervals
Refer to the maintenance plan on the
following pages for the required maintenance
intervals.
NOTE:
Once you have carried out the last intervention in the table, continue with the scheduled servicing, maintaining the frequency indicated in
the plan by marking each operation with a dot or dedicated note. Simply restarting the maintenance from the start of the plan may cause the
allowed interval to be exceeded for some operations.
CAUTION!

Failure to perform the required maintenance
items may result in damage to the vehicle.

At Every Oil Change Interval As Indicated By Oil Change Indicator System:
Change oil and filter
Rotate the tires. Rotate at the first sign of irregular wear, even if it occurs before the oil indicator system turns on
Inspect battery and clean and tighten terminals as required
Inspect the CV/Universal joints
Inspect brake pads, shoes, rotors, drums, hoses and park brake
Inspect engine cooling system protection and hoses
Inspect exhaust system
Inspect engine air cleaner if using in dusty or off-road conditions
Inspect all door latches for presence of grease, reapply if necessary.
Inspect coolant level.
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SERVICING AND MAINTENANCE
218Mileage or time passed (whichever comes first)
12,500
25,000
37,500
50,000
62,500
75,000
87,500
100,000
112,500
125,000
137,500
150,000
162,500
175,000
187,500
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
200,000
220,000
240,000
260,000
280,000
300,000
Additional Inspections
Change the engine oil and engine oil filter. (*)
Inspect the CV/Universal joints. X X X X X X X X X X X X X X X
Inspect front suspension, rear suspension, boot seals,
tie rod ends, and replace if necessary. X X X X X X X
Visually inspect condition of: exterior bodywork,
underbody protection, pipes and hoses (exhaust - fuel
system - brakes), rubber elements (boots, sleeves,
bushings, etc.). X X X X X X X
If using your vehicle in dusty or off-road conditions,
inspect the air cleaner filter, and replace if necessary. X X X X X X X X X X X X X X X
Inspect the brake linings, parking brake function. X X X X X X X
Check and, if necessary, top up fluid levels. (°) X X X X X X X X X X X X X X X
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219
Additional Maintenance
Replace engine air cleaner filter.X X X X X X X
Replace air conditioning/cabin air filter. X X X X X X X
Change brake fluid every 24 months if using DOT 4
brake fluid. (**) X X X X X X X
Replace the engine fuel filter. X X X X X X X
Inspect accessory drive and timing belt. XX X
Replace accessory drive belt. (***) XX
Flush and replace the engine coolant at 10 years or
150,000 miles (240,000 km) whichever comes first. X X
Replace timing drive belt. (***) XX
Mileage or time passed (whichever comes first)
12,500
25,000
37,500
50,000
62,500
75,000
87,500
100,000
112,500
125,000
137,500
150,000
162,500
175,000
187,500
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
200,000
220,000
240,000
260,000
280,000
300,000
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SERVICING AND MAINTENANCE
220
(*) The actual interval for changing engine
oil and replacing the engine oil filter
depends on the vehicle usage conditions,
and is signaled by the warning light or
message in the instrument panel. In any
case, it must never exceed 12,500 miles
(20,000 km) or 1 year.
(**) The brake fluid interval is time based
only, mileage intervals do not apply.(***) The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance traveled.
The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use (dusty
areas, severe weather conditions, very low or
very high temperatures for extended periods,
city driving, long periods of idling). Under no
circumstances should these intervals be
exceeded.
(°) Consumption of additive AdBlue®
(UREA) depends on the condition of use of
the vehicle and is indicated by LED and/or
message on the instrument panel. WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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221
ENGINE COMPARTMENT
2.0L Gasoline Engine
1 — Brake Fluid Reservoir7 — Battery
2 — Intercooler Coolant Reservoir 8 — Power Distribution Center (Fuses)
3 — Intercooler Coolant Pressure Cap 9 — Washer Fluid Reservoir
4 — Engine Oil Fill 10 — Power Steering Fluid Reservoir
5 — Engine Coolant Reservoir 11 — Engine Oil Dipstick
6 — Engine Coolant Pressure Cap 12 — Engine Air Cleaner
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