WARNINGS
To reduce the risk of personal injury,
make sure the engine is cool before
unscrewing the coolant pressure relief cap.
The cooling system is under pressure. Steam
and hot liquid can come out forcefully when
you loosen the cap slightly.
Do not add coolant further than the
MAX mark.
Checking the Engine Coolant
When the engine is cold, check the
concentration and level of the engine coolant
at the intervals listed in the scheduled
maintenance information. See Scheduled
Maintenance (page 353).
Note: Make sure that the coolant level is
between the MIN and MAX marks on the
coolant reservoir.
Note: Coolant expands when it is hot. The
level may extend beyond the MAX mark.
Note: If the level is at the MIN mark, below
the MIN mark, or empty, add coolant
immediately.
Maintain coolant concentration within 48%
to 50%, which equates to a freeze point
between -30°F (-34°C) and -34°F (-37°C).
Note: For best results, coolant concentration
should be tested with a refractometer such
as Robinair® Coolant and Battery
Refractometer 75240. We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentrations.
Note: Automotive fluids are not
interchangeable. Do not use engine coolant,
antifreeze or windshield washer fluid outside
of its specified function and vehicle location.
Adding Engine Coolant
Note: Do not use stop leak pellets, cooling
system sealants or additives as they can
cause damage to the engine cooling or
heating systems. Your warranty may not
cover these damages.
Note: During normal vehicle operation, the
coolant may change color from orange to
pink or light red. As long as the coolant is
clear and uncontaminated, this color change
does not indicate the coolant has degraded
nor does it require the coolant to be drained,
the system to be flushed, or the coolant to
be replaced.
Do not mix different colors or types of
coolant in your vehicle. Mixing of engine
coolants may harm your engine’s cooling
system. Use prediluted engine coolant
meeting the correct specification. See
Capacities and Specifications (page 328).
The use of an incorrect coolant may harm
the engine or cooling system components
and may not be covered by the vehicle
Warranty.
In case of emergency, you can add a large
amount of water without engine coolant in
order to reach a vehicle service location. In
this instance, qualified personnel:
1. Must drain the cooling system.
2. Chemically clean the cooling system with
Motorcraft Premium Cooling System
Flush.
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Navigator (TB5) Canada/United States of America, enUSA, First Printing
Maintenance