Pineapple Cake

1 (18.25 ounce) box Duncan Hines Butter
    Recipe Golden cake mix
1 (11 ounce) can mandarin oranges with juice
4 eggs
1 1/2 cups vegetable oil
1 (15 1/2 ounce) can crushed pineapple with juice
1 small box vanilla instant pudding
1 (13 1/2 ounce) container Cool Whip