Thunderstorm Gray 2025 GMC Sierra 3500HD AT4 4D Crew Cab 4WD 10-Speed Automatic Duramax 6.6L V8 Turbodiesel Contact Handy Buick GMC for details on this vehicle today! Reach out to us at 802-524-4615, speak with one of our customer friendly purchase and leasing consultants to schedule the test drive of your next NEW or PRE-OWNED vehicle! Please Note: New vehicles marked as In Transit and other recent additions to our inventory may not show all available rebates, discounts and incentives..