2005 Dodge Neon Owner's Manual - Page 182
2005 Dodge Neon Manual
Page 182 highlights
182 MAINTAINING YOUR VEHICLE CAUTION! Mixing of coolants other than specified (nonHOAT), may result in engine damage that may not be covered under the new vehicle warranty, and decreased corrosion protection. If a non-HOAT coolant is introduced into the cooling system in an emergency, it should be replaced with the specified coolant as soon as possible. Do not use plain water alone or alcohol base antifreeze products. Do not use additional rust inhibitors or antirust products, as they may not be compatible with the radiator coolant and may plug the radiator. This vehicle has not been designed for use with Propylene Glycol based coolants. Use of Propylene Glycol based coolants is not recommended. Adding Coolant When adding coolant, a minimum solution of 50% ethylene glycol antifreeze coolant in water should be used. 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/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. Cooling System Pressure Cap The cap must be fully tightened to prevent loss of coolant, and to insure that coolant will return to the radiator from the coolant reserve tank.