2009 Dodge Ram 2500 Pickup Owner Manual - Page 446

444 MAINTAINING YOUR VEHICLE When adding engine coolant (antifreeze): • The manufacturer recommends using MOPAR௡ Antifreeze/Coolant 5 Year/100,000 Mile Formula HOAT (Hybrid Organic Additive Technology). • Mix a minimum solution of 50% HOAT engine coolant (antifreeze) and distilled water. Use higher concentrations (not to exceed 70%) if temperatures below -34°F (-37°C) are anticipated. • Use only high purity water such as distilled or deionized water when mixing the water/engine coolant (antifreeze) solution. The use of lower quality water will reduce the amount of corrosion protection in the engine cooling system. Please note that it is the owner's responsibility to maintain the proper level of protection against freezing according to the temperatures occurring in the area where the vehicle is operated. NOTE: Mixing engine coolant (antifreeze) types will decrease the life of the engine coolant (antifreeze) and will require more frequent engine coolant (antifreeze) changes. Cooling System Pressure Cap The cap must be fully tightened to prevent loss of engine coolant (antifreeze), and to ensure that engine coolant (antifreeze) will return to the radiator from the coolant recovery bottle. The cap should be inspected and cleaned if there is any accumulation of foreign material on the sealing surfaces.