In a large bowl, stir together cake mix, instant pudding, and rolled oats. Add oil, sour cream, water, and vanilla; mix until smooth and well blended. Stir in chocolate chips. Roll dough into 1 1/2 inch balls, and place 2 inches apart on the prepared cookie sheets.
Bake for 8 to 10 minutes in the preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.