2015 JEEP WRANGLER Owners Manual

NOTE:
•Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could
lead to severe internal engine damage. If any coolant is
needed to be added to the system please contact your
local authorized dealer.
•Mixing engine coolant (antifreeze) types is not recom-
mended and can result in cooling system damage. If
HOAT and OAT coolant are mixed in an emergency,
have a authorized dealer drain, flush, and refill with
OAT coolant (conforming to MS-12106) as soon as
possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant
(antifreeze) will return to the radiator from the coolant
recovery tank.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
•Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is
overheated. Do not loosen or remove the cap to cool
an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scalding
or injury, do not remove the pressure cap while the
system is hot or under pressure.
•Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.7
MAINTAINING YOUR VEHICLE 615

Disposal Of Used Engine Coolant
Used ethylene glycol-based engine coolant (antifreeze) is
a regulated substance requiring proper disposal. Check
with your local authorities to determine the disposal
rules for your community. To prevent ingestion by ani-
mals or children, do not store ethylene glycol-based
engine coolant in open containers or allow it to remain in
puddles on the ground. If ingested by a child or pet, seek
emergency assistance immediately. Clean up any ground
spills immediately.
Engine Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine idling, and warm to normal operating tempera-
ture, the level of the engine coolant (antifreeze) in the
bottle should be between the ranges indicated on the
bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
engine coolant (antifreeze) freeze point or replacing en-
gine coolant (antifreeze). Advise your service attendant
of this. As long as the engine operating temperature is
satisfactory, the coolant bottle need only be checked once
a month.
When additional engine coolant (antifreeze) is needed to
maintain the proper level, it should be added to the
coolant bottle. Do not overfill.
Points To Remember
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 nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot engine
coolant (antifreeze) to enter the radiator.
616 MAINTAINING YOUR VEHICLE

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 (anti-
freeze) needs to be added, the contents of the coolant
expansion bottle must also be protected against freez-
ing.
•If frequent engine coolant (antifreeze) additions are
required, the cooling system should be pressure tested
for leaks.
•Maintain engine coolant (antifreeze) concentration
at a minimum of 50% OAT coolant (conforming to
MS-12106) 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 coolant (antifreeze)
performance, poor gas mileage, and increased emis-
sions.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
7
MAINTAINING YOUR VEHICLE 617

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.
Power Disc Brakes
Disc brakes do not require adjustment; however, several
hard stops during the break-in period are recommended
to seat the linings and wear off any foreign material.
Brake Master Cylinder
The fluid level in the master cylinders should be checked
whenever the vehicle is serviced. If necessary, add fluid
to bring level to the full level mark on the side of the
reservoir of the brake master cylinder. With disc brakes,
fluid level can be expected to fall as the brake pads wear.
If the brake fluid level is abnormally low, check system
for leaks.
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
WARNING!
•Use only manufacturer’s recommended brake
fluid. Refer to “Fluids, Lubricants, and Genuine
Parts” in “Maintaining Your Vehicle” for further
information. 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.
(Continued)
618 MAINTAINING YOUR VEHICLE

WARNING!(Continued)
•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 a open container absorbs moisture from the
air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a collision.
•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.
(Continued)
WARNING!(Continued)
•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.
Automatic Transmission — If Equipped
Selection Of Lubricant
It is important to use the proper transmission fluid to
ensure optimum transmission performance and life. Use
only the manufacturer’s specified transmission fluid.
Refer to “Fluids, Lubricants, and Genuine Parts” in this
section for fluid specifications. It is important to maintain
the transmission fluid at the correct level using the
recommended fluid.
7
MAINTAINING YOUR VEHICLE 619

NOTE:No chemical flushes should be used in any
transmission; only the approved lubricant should be
used.
CAUTION!
Using a transmission fluid other than the manufac-
turer’s recommended fluid may cause deterioration
in transmission shift quality and/or torque converter
shudder, and will require more frequent fluid and
filter changes. Refer to “Fluids, Lubricants, and
Genuine Parts” in this section for fluid specifica-
tions.
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 supple-
mental additives. Therefore, do not add any fluid addi-
tives to the transmission. The only exception to this
policy is the use of special dyes for diagnosing fluid
leaks. Avoid using transmission sealers as they may
adversely affect seals.
CAUTION!
Do not use chemical flushes in your transmission as
the chemicals can damage your transmission compo-
nents. Such damage is not covered by the New
Vehicle Limited Warranty.
Fluid Level Check
It is best to check the fluid level when the transmission
is at normal operating temperature (approximately
180° F/82° C). This occurs after at least 15 miles (25 km)
620 MAINTAINING YOUR VEHICLE

of driving. At normal operating temperature, the fluid
cannot be held comfortably between the fingertips.
Use the following procedure to check the transmission
fluid level properly:
1. Park the vehicle on level ground.
2. Remove the engine cover by pulling it up off the
mounting studs (two in the front and two in the rear).
3. Run the engine at idle speed and normal operating
temperature.
4. Fully apply the parking brake, and press the brake
pedal.
5. Place the shift lever momentarily into each gear posi-
tion (allowing time for the transmission to fully en-
gage in each position), ending with the transmission in
PARK.
6. Remove the dipstick, wipe it clean and reinsert it until
seated.
7. Remove the dipstick again and note the fluid level on
both sides. The fluid level reading is only valid if there
is a solid coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full of fluid
if the actual level is at or above the hole. The fluid level
should be between the HOT (upper) reference holes on
the dipstick at normal operating temperature. If the
fluid level is low, add fluid through the dipstick tube
to bring it to the proper level.Do not overfill.Use
ONLY the specified fluid (refer to#Fluids, Lubricants,
and Genuine Parts#for fluid specifications). After
adding any quantity of oil through the dipstick tube,
wait a minimum of two minutes for the oil to fully
drain into the transmission before rechecking the fluid
level.
7
MAINTAINING YOUR VEHICLE 621

NOTE:
•The holes in the dipstick will be full of fluid if the
actual level is at or above the hole.
•If it is necessary to check the transmission below the
operating temperature, the fluid level should be
between the two COLD (lower) holes on the dipstick
with the fluid at approximately 80° F (27° C). If the
fluid level is correctly established at 80° F (27° C), it
should be between the HOT (upper) reference holes
when the transmission reaches 180° F (82° C). Re-
member it is best to check the level at the normal
operating temperature.
CAUTION!
If the fluid temperature is below 50°F (10°C) it may
not register on the dipstick. Do not add fluid until
(Continued)
CAUTION!(Continued)
the temperature is elevated enough to produce an
accurate reading. Run the engine at idle, in PARK, to
warm the fluid.
8. Reinstall the engine cover and snap it down securely
onto the four mounting studs.
9. Check for leaks. Release the parking brake.
NOTE:To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
sure that the dipstick cap is properly reseated. It is
normal for the dipstick cap to spring back slightly from
its fully seated position, as long as its seal remains
engaged in the dipstick tube.
Fluid And Filter Changes
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
622 MAINTAINING YOUR VEHICLE