RAM 2500 Truck 2WD V8-5.7L VIN D (2004)
Pure Water-Water can absorb more heat than a mixture of water and ethylene-glycol. This is for purpose of heat transfer only. Water also freezes at a
higher temperature and allows corrosion.
100 percent Ethylene-Glycol-The corrosion inhibiting additives in ethylene-glycol need the presence of water to dissolve. Without water, additives
form deposits in system. These act as insulation causing temperature to rise to as high as 149°C (300°F). This temperature is hot enough to melt
plastic and soften solder. The increased temperature can result in engine detonation. In addition, 100 percent ethylene-glycol freezes at -22°C (-8°F).
50/50 Ethylene-Glycol and Water-Is the recommended mixture, it provides protection against freezing to -37°C (-34°F). The antifreeze concentration
must always be a minimum of 44 percent, year round in all climates. If percentage is lower, engine parts may be eroded by cavitation. Maximum
protection against freezing is provided with a 68 percent antifreeze concentration, which prevents freezing down to -67.7°C (-90°F). A higher
percentage will freeze at a warmer temperature. Also, a higher percentage of antifreeze can cause the engine to overheat because specific heat of
antifreeze is lower than that of water.
CAUTION: Richer antifreeze mixtures cannot be measured with normal field equipment and can cause problems associated with 100 percent
ethylene-glycol.
COOLANT SELECTION AND ADDITIVES
The use of aluminum cylinder blocks, cylinder heads and water pumps requires special corrosion protection. Only Mopar Antifreeze/Coolant, 5
Year/100,000 Mile Formula (glycol base coolant with corrosion inhibitors called HOAT, for Hybrid Organic Additive Technology) is recommended.
This coolant offers the best engine cooling without corrosion when mixed with 50% distilled water to obtain to obtain a freeze point of -37°C (-35°F).
If it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solution.
CAUTION: Do not use coolant additives that are claimed to improve engine cooling.
OPERATION
Coolant flows through the engine block absorbing the heat from the engine, then flows to the radiator where the cooling fins in the radiator transfers
the heat from the coolant to the atmosphere. During cold weather the ethylene-glycol or propylene-glycol coolant prevents water present in the cooling
system from freezing within temperatures indicated by mixture ratio of coolant to water.
