Boil salted water in a large pot. Add elbow macaroni and cook for 7-8 minutes until al dente. Drain and rinse under cold water to cool.

In a large mixing bowl, combine mayonnaise, mustard, vinegar, and sugar. Whisk until smooth for 1-2 minutes.

Fold cooled macaroni into the dressing. Add pickle relish, chopped eggs, and diced celery. Stir carefully to combine.

Cover with plastic wrap or transfer to an airtight container. Refrigerate for at least 2 hours or overnight.

Before serving, stir salad and adjust dressing if needed. Serve chilled at BBQs or gatherings.