2011 Ford F450 Super Duty Crew Cab Owner Guide 4th Printing - Page 379

Maintenance and Specifications If your vehicle is equipped with a diesel engine, refer to the Maintenance product specifications and capacities section of your diesel supplement. Fill your engine coolant reservoir as outlined previously in the Adding engine coolant section. Severe climates If you drive in extremely cold climates: • It may be necessary to increase the coolant concentration above 50%. • NEVER increase the coolant concentration above 60%. • A coolant concentration of 60% will provide improved freeze point protection. 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%. • 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 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. 379 2011 F-250/350/450/550 (f23) Owners Guide, 4th Printing USA (fus)