3500 4x2 Pickup L6-359 5.9L DSL Turbo (1994)
Coolant: Description and Operation
Use antifreeze during all seasons to protect the cooling system from corrosion as well as freezing damage. The antifreeze should be changed every two
years.
A mixture of 50% water and 50% ethylene-glycol base antifreeze is required for operation of the engine in temperature environments above 37°C [-34°
F]. A mixture of 40% water and 60% antifreeze is recommended for temperatures below -37°C [-34°F].
NOTE: In tropical climates where antifreeze availability may be limited, use a corrosion inhibitor (Cummins Liquid DCA, or an equivalent) to protect
the engine cooling system.