Cook noodles according to package directions. Drain; rinse with cold water. Drain again.
In a bowl, combine noodles, apples, carrots, the chopped sweet pickles, the eggs, and onion.
For dressing, stir together the mayonnaise or salad dressing, sour cream, and salt. Add to the noodle mixture and toss to coat. Cover and chill in the refrigerator for at least 2 hours or up to 24 hours. If necessary, stir in some milk to make desired consistency.
Serve in a bowl or on a platter. Garnish with the sweet pickle slices, if you like. Makes 12 to 16 side-dish servings.