Preheat the grill to medium-high heat. Lightly oil the grill grates to prevent sticking.
Grill the corn for about 10-12 minutes, turning occasionally until charred and tender. Grill the zucchini slices for about 3-4 minutes on each side until grill marks appear. Remove both from the grill and let cool slightly.
Once the corn is cool enough to handle, cut the kernels off the cob and place them in a large mixing bowl. Add the grilled zucchini, diced red bell pepper, cherry tomatoes, red onion, and fresh basil.
In a separate small bowl, whisk together the sun-dried tomatoes, olive oil, red wine vinegar, Dijon mustard, salt, and pepper until well combined.
Pour the vinaigrette over the salad and toss gently to combine all ingredients.
Serve immediately or refrigerate for 30 minutes to allow the flavors to meld.