Mashed Potato Salad

6 c. mashed potatoes (instant mashed potatoes can be used)
4 hard-boiled eggs
3/4 c. chopped celery
3/4 c. chopped pickles
1 1/2 c. salad dressing (Miracle Whip)
1/4 c. sugar
1/4 c. vinegar
salt and pepper to taste

In a large bowl, mix mashed potatoes, chopped eggs, celery and pickles. In a small bowl, mix salad dressing, sugar and vinegar until well blended. Mix dressing into potatoes and chill.