2011 Ford Expedition Owner Guide 1st Printing - Page 332

Maintenance and Specifications • A coolant concentration of 60% will provide freeze point protection down to -62°F [-52°C]. Increased engine coolant concentrations above 60% will decrease the overheat protection characteristics of the engine coolant and may cause engine damage. • If available, refer to the chart on the coolant container to ensure the coolant concentration in your vehicle will provide adequate freeze protection at the temperatures in which you drive in the winter months. 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%. • A coolant concentration of 40% will provide freeze point protection down to -12°F [-24°C]. Decreased engine coolant concentrations below 40% will decrease the corrosion/freeze protection characteristics of the engine coolant and may cause engine damage. • If available, 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 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 engine coolant temperature • The symbol will illuminate. indicator 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. 332 2011 Expedition (exd) Owners Guide, 1st Printing USA (fus)