Drain pineapple and cherries, reserving juices. Bring reserved juices and cola to a boil in a saucepan over medium-high heat; stir in gelatin. Remove from heat; stir 2 minutes or until gelatin dissolves.
Stir in pineapple, cherries, and pecans; pour into a lightly greased 6 1/2-cup mold. Cover and chill 8 hours. Unmold onto a serving dish.