2004 Dodge Ram 3500 Pickup Owner's Manual - Page 345

MAINTAINING YOUR VEHICLE 345 The radiator normally remains completely full, so there is no longer a need to remove the coolant pressure cap except for checking coolant freeze point or replacement with new antifreeze coolant. WARNING! Never add coolant to the radiator when the engine is overheated. Do not loosen or remove pressure cap to cool an overheated engine! The coolant is under pressure and severe scalding could result. Drain, Flush And Refill At intervals shown on the Maintenance Schedules, the system should be drained, flushed and refilled. Refer to your dealer or consult a service manual for proper procedures. Adding Coolant When adding coolant or refilling system, a 50% solution of ethylene glycol antifreeze coolant in water should be used. Higher concentrations (not to exceed 65%) are required if temperatures below -34 F° (-37 C°) are anticipated. Use only high purity water such as distilled or deionized water when mixing the water/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 coolant types will decrease the life of the engine coolant and will require more frequent coolant changes. 7