Bring a pot of salted water to a boil and cook the pasta according to the instructions on the package until it is al dente. Once cooked, drain the pasta and toss it with 1/4 cup of dill pickle juice. Allow it to sit for 5-10 minutes to soak up the flavor, then remove any excess liquid.
In a small bowl, mix together the Greek yogurt, sour cream, 2 1/2 tablespoons of dill pickle juice, 3/4 teaspoon garlic powder, 1/4 teaspoon onion powder, salt, and pepper. Adjust the seasoning to your liking.
In a large mixing bowl, add the pasta, chopped dill pickles, red onion, cheddar cheese (if using), and fresh dill. Mix well to combine. Spoon the dressing over the pasta mixture and stir gently until everything is evenly coated.
Cover the bowl and place it in the refrigerator for at least 1 hour to allow the flavors to blend together.
Garnish with extra fresh dill, if desired, and serve chilled.