Jeep Wrangler Owner's Manual page 238

 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 an
authorized dealer.
Adding Coolant
Your vehicle has been built with an improved engine
coolant (OAT coolant conforming to MS.90032) that
allows extended maintenance intervals. This engine
coolant (antifreeze) can be used up to 10 years or
150,000 miles (240,000 km) before replacement. To
prevent reducing this extended maintenance period, it is
important to use the same engine coolant (OAT coolant
conforming to MS.90032) throughout the life of your
vehicle.
Please review these recommendations for using Organic
Additive Technology (OAT) engine coolant that meets the
requirements of the manufacturer Material Standard
MS.90032. When adding engine coolant:
 We recommend using Mopar® Antifreeze/Coolant
10 Year/150,000 Mile (240,000 km) Formula OAT
that meets the requirements of the manufacturer
Material Standard MS.90032.
 Mix a minimum solution of 50% OAT engine coolant
that meets the requirements of the manufacturer
Material Standard MS.90032 and distilled water. Use
higher concentrations (not to exceed 70%) if tempera-
tures below −34°F (−37°C) are anticipated. Please
contact an authorized dealer for assistance.
 Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.
The use of lower quality water will reduce the amount
of corrosion protection in the engine cooling system.
NOTE:
 It is the owner's responsibility to maintain the proper
level of protection against freezing according to the
temperatures occurring in the area where the vehicle is
operated.
 Use care when filling under hood fluids such as engine
oil, windshield washer solvent, antifreeze, etc., to mini-
mize spillage onto the top of the engine. Any excess
fluid that is spilled onto the top of the engine should be
removed using compressed air or an absorbent cloth.
 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 an
authorized dealer.
 Mixing engine coolant types is not recommended and
can result in cooling system damage. If HOAT and OAT
coolant are mixed in an emergency, have an authorized
dealer drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as possible.
SERVICING AND MAINTENANCE
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant will
return to the radiator from the coolant expansion bottle/
recovery tank (if equipped).
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 over-
heated. 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 speci-
fied for your vehicle. Personal injury or engine
damage may result.
Disposal Of Used Coolant
Used ethylene glycol-based 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 animals or
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