2/3 cup Sugar
2/3 cup Water
1 cup Grapefruit juice
1/2 cup Orange juice
3 tablespoons Grenadine syrup
28 ounces Ginger ale -- chilled
Combine sugar and water in saucepan over low heat. Stir until sugar is dissolved. Bring to boil and boil 10 minutes. Cool. Add sugar syrup to grapefruit and orange juices. Chill thoroughly. Add grenadine and ginger ale just before serving.