2018-Navigator-Owners-Manual

Maintenance

Severe Climates If you drive in extremely cold climates: • It may be necessary to increase the coolant concentration above 50%. • A coolant concentration of 60% provides improved freeze point protection. Coolant concentrations above 60% decrease the overheat protection characteristics of the coolant and may cause engine damage. If you drive in extremely hot climates: • You can decrease the coolant concentration to 40%. • Coolant concentrations below 40% decrease the freeze and corrosion protection characteristics of the coolant and may cause engine damage. Vehicles driven year-round in non-extreme climates should use prediluted coolant for optimum cooling system and engine protection.

Coolant Change At specific mileage intervals, as listed in the scheduled maintenance information, the coolant should be changed. Add prediluted coolant approved to the correct specification. See Capacities and Specifications (page 422). Fail-Safe Cooling Fail-safe cooling allows you to temporarily drive your vehicle before any incremental component damage occurs. The fail-safe distance depends on ambient temperature, vehicle load and terrain. How Fail-Safe Cooling Works

• Brine. • Any coolant mixed with alcohol or methanol antifreeze. Alcohol and other liquids can cause engine damage from overheating or freezing. Do not add extra inhibitors or additives to the coolant. These can be harmful and compromise the corrosion protection of the coolant. Recycled Coolant We do not recommend the use of recycled coolant as an approved recycling process is not yet available. Dispose of used engine coolant in an appropriate manner. Follow your community's regulations and standards for recycling and disposing of automotive fluids.

If the engine begins to overheat, the coolant temperature gauge moves toward the red zone: A warning lamp illuminates and a message may appear in the information display.

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Navigator (TB9) Canada/United States of America, enUSA, Edition date: 201708, First Printing