2015 Ford F150 SuperCrew Cab Owner Manual Printing 1 - Page 308

Maintenance 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. 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. What You Should Know About FailSafe 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 305 F-150 (), enUSA, First Printing