Ford F-150 Owner's Manual page 289

If you drive in extremely hot climates:
• It is still necessary to maintain the coolant concentration
above 40%.
• NEVER decrease the coolant concentration below 40%.
• Decreased engine coolant concentrations below 40% will
decrease the corrosion protection characteristics of the engine
coolant and may cause engine damage.
• Decreased engine coolant concentrations below 40% will
decrease the freeze protection characteristics of the engine
coolant and may cause engine damage.
• Refer to the chart on the coolant container to ensure the
coolant concentration in your vehicle will provide adequate
protection at the temperatures in which you drive.
Vehicles driven year-round in non-extreme climates should use a 50/50
mixture of engine coolant and distilled water for optimum cooling system
and engine protection.
What you should know about fail-safe cooling (if equipped)
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.
• The mini message center (if
equipped) will indicate "Check
Gauges", refer to Warning Lights
and Chimes in the Instrument Cluster chapter.
• The message center (if equipped) will indicate a system warning, refer
to Message Center in the Driver Controls chapter.
• The
light 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.
2006 F-150 (f12)
Owners Guide (post-2002-fmt)
USA (fus)
Maintenance and Specifications
289