•
A coolant concentration of 40% will provide improved overheat
protection. Engine coolant concentrations below 40% will decrease the
corrosion/freeze protection characteristics of the engine coolant and
may cause engine damage.
Vehicles driven year-round in non-extreme climates should use
prediluted engine coolant for optimum cooling system and engine
protection.
What You Should Know About Fail-Safe Cooling
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The fail-safe distance depends on ambient temperatures, vehicle load and
terrain.
How Fail-Safe Cooling Works
If the engine begins to overheat, the engine coolant temperature gauge
will move to the red (hot) area and:
The coolant temperature warning light will illuminate.
The service engine soon indicator will illuminate.
If the engine reaches a preset over-temperature condition, the engine
will automatically switch to alternating cylinder operation. Each disabled
cylinder acts as an air pump and cools the engine.
When this occurs the vehicle will still operate. However:
•
The engine power will be limited.
•
The air conditioning system will be disabled.
Continued operation will increase the engine temperature and the engine
will completely shut down, causing steering and braking effort to
increase.
Once the engine temperature cools, the engine can be restarted. Take
your vehicle to an authorized dealer as soon as possible to minimize
engine damage.
280
Maintenance
2014 Expedition
(exd)
Owners Guide gf, 2nd Printing, November 2013
USA
(fus)
