FORD 2015 F-150 - Manual (Page 308)

Severe Climates
If you drive in extremely cold climates:
•
It may be necessary to have a Ford
authorized dealer increase the coolant
concentration above 50%.
• A coolant concentration of 60%
provides improved freeze point
protection. Engine coolant
concentrations above 60% decrease
the overheat protection characteristics
of the engine coolant and may cause
engine damage.
If you drive in extremely hot climates:
•
It may be necessary to have a Ford
authorized dealer decrease the coolant
concentration to 40%.
• A coolant concentration of 40%
provides improved overheat protection.
Engine coolant concentrations below
40% will decrease the freeze and
corrosion 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 you deplete the engine coolant supply,
fail-safe cooling allows you to temporarily
drive your vehicle before you incur
incremental component damage. 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
automatically switches to alternating
cylinder operation. Each disabled cylinder
acts as an air pump and cools the engine.
When this occurs, your vehicle will still
operate. However:
•
The engine power will be limited.
• This will disable the air conditioning
system.
Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.
When the engine temperature cools, you
can re-start your engine. Take your vehicle
to an authorized dealer as soon as possible
to minimize engine damage.
When Fail-Safe Mode Is Activated
WARNINGS
Fail-safe mode is for use during
emergencies only. Operate your
vehicle in fail-safe mode only as long
as necessary to bring your vehicle to rest
in a safe location and seek immediate
repairs. When in fail-safe mode, your
vehicle will have limited power, will not be
able to maintain high-speed operation, and
may completely shut down without
warning, potentially losing engine power,
power steering assist, and power brake
assist, which may increase the possibility
of a crash resulting in serious injury.
Never remove the coolant reservoir
cap while the engine is running or hot.
305
F-150 (), enUSA, First Printing
Maintenance