Legacy GMC of Waxahachie stocks new GMC Sierra 2500 HD and Sierra 3500 HD heavy-duty pickups at 1701 US-287 Byp, a straight run up US-287 from Corsicana and Navarro County. Our heavy-duty inventory covers multiple cab styles, bed lengths, and both gas and diesel powertrains — from single rear wheel 2500 HD crew cabs for job-site work to dual rear wheel 3500 HD duallies built for serious gooseneck trailering. Call our sales team at 214-903-4359 to check what’s on the ground today.
Seven trims span the 2500 HD and 3500 HD; AT4X is 2500 HD only. The lineup below is the 2026 model year.
| Trim | Standard Engine | Built For |
|---|---|---|
| Pro | 6.6L V8 gas | Fleet and job-site work |
| SLE | 6.6L V8 gas | Added comfort, same capability |
| SLT | 6.6L V8 gas | Leather, larger displays, standard MultiPro Tailgate |
| AT4 | 6.6L V8 gas | Off-road hardware and capability |
| AT4X | 6.6L V8 gas | Maximum off-road spec — 2500 HD only |
| Denali | 6.6L V8 gas | Open-pore wood, Forge perforated leather, Bose audio |
| Denali Ultimate | 6.6L Duramax turbo-diesel | Alpine Umber leather, 16-way massaging seats |
The Duramax turbo-diesel is available on every trim and standard on Denali Ultimate. For a full trim-by-trim breakdown, see our 2026 Sierra 2500 HD trims and pricing guide.
Cited Source: GMC Sierra 2500HD & 3500HD — trim lineup | GM Authority — 2026 model year trim and engine availability, published October 7, 2026
Two 6.6-liter V8 engines power the 2026 Sierra HD. The standard gas V8 produces 401 horsepower and 464 lb-ft of torque — enough for everyday hauling and medium-duty towing. The available Duramax turbo-diesel V8 delivers 470 horsepower and 975 lb-ft, the engine to order if you’re pulling equipment, livestock, or multi-car trailers. Both pair with the Allison 10-speed automatic, standard across the lineup, with Tow/Haul mode and Auto Grade Braking for control on descents.
Compare both powertrains in our Sierra 2500 HD engine options guide.
Cited Source: GMC Sierra 2500HD & 3500HD — engine and transmission specifications
2026 Sierra HD maximum ratings, properly equipped:
| Capability | Sierra 2500 HD | Sierra 3500 HD |
|---|---|---|
| Max conventional towing§ | Up to 20,000 lbs | Up to 20,000 lbs |
| Max fifth-wheel towing§ | Up to 22,390 lbs | Up to 36,000 lbs |
| Max gooseneck towing§ | Up to 22,390 lbs | Up to 32,000 lbs |
| Max payload§ | Up to 4,049 lbs | Up to 7,290 lbs |
| Rear axle | Single rear wheel | Single or dual rear wheel |
§ Maximum towing and payload capacity figures are based on properly equipped vehicles and vary by configuration. Do not exceed any weight rating. See your owner’s manual and the vehicle’s door-jamb label for specific capacities.
On the 3500 HD, hitch type changes the number: the 36,000-lb peak requires a fifth-wheel hitch, while the same truck is rated at 32,000 lbs with a gooseneck — plan around 32,000. Ratings also vary by cab, bed, drivetrain, axle ratio, and package. A 2500 HD crew cab is rated up to 21,870 lbs; the 22,390-lb peak needs a Regular Cab Long Bed 2WD diesel with the Max Trailering Package.
Dig into the numbers in our Sierra 2500 HD towing capacity guide and Sierra 3500 HD towing capacity guide, or see how it stacks up in our Sierra 2500HD vs. Ram 2500 comparison.
Cited Source: GMC Sierra HD Pro, SLE & SLT — gooseneck/fifth-wheel ratings and payload | GM Authority — configuration-level trailering tables
In-Vehicle Trailering App with pre-departure checklists, trailer light test, and trailer tire pressure monitoring.
Up to 14 available camera views, including Transparent Trailer View, which pairs a trailer-mounted camera with the tailgate camera to see past a hitched trailer.
Simplifies gooseneck and fifth-wheel hitch alignment.
¶ Driver-assist and safety systems are supplemental aids and are not a substitute for safe, attentive driving. Their effectiveness depends on weather, road, and traffic conditions and other factors. Always obey traffic laws and stay attentive to the road. See your owner’s manual for system details and limitations.
Cited Source: GMC Sierra HD — ProGrade Trailering and camera systems
If the configuration you want isn’t on the lot, our sales team can place a factory order — including colors such as Onyx Black and Titanium Rush Metallic and equipment like the Max Trailering Package. Call 214-903-4359 to check incoming units or start a build.
Both share cab choices and the same 6.6-liter engines. The 3500 HD adds an available dual rear wheel axle, which spreads payload and trailer tongue weight across four rear tires. That raises maximum payload to 7,290 lbs and maximum fifth-wheel towing to 36,000 lbs.§
New Sierra HD trucks carry a 3-year/36,000-mile bumper-to-bumper limited warranty. Powertrain and roadside assistance coverage run 5 years/60,000 miles on gas models and 5 years/100,000 miles on 6.6L Duramax turbo-diesel models.
| Coverage | 6.6L V8 gas | 6.6L Duramax turbo-diesel |
|---|---|---|
| Bumper-to-bumper limited warranty‖ | 3 years / 36,000 miles | 3 years / 36,000 miles |
| Powertrain limited warranty‖ | 5 years / 60,000 miles | 5 years / 100,000 miles |
| 24/7 roadside assistance‖ | 5 years / 60,000 miles | 5 years / 100,000 miles |
‖ This information is provided for general educational purposes only and does not constitute legal advice. Warranty coverage depends on the specific terms of your vehicle’s warranty agreement. Consult your owner’s manual or a qualified legal professional for guidance on your individual situation.
Cited Source: GMC Important Information — warranty and roadside assistance terms
Drivers from Corsicana, Ennis, Midlothian, DeSoto, and Arlington can see our full heavy-duty inventory at 1701 US-287 Byp in Waxahachie. Call 214-903-4359 to confirm availability or schedule a test drive.
§ Maximum towing and payload capacity figures are based on properly equipped vehicles and vary by configuration. Do not exceed any weight rating. See your owner’s manual and the vehicle’s door-jamb label for specific capacities.
¶ Driver-assist and safety systems are supplemental aids and are not a substitute for safe, attentive driving. Their effectiveness depends on weather, road, and traffic conditions and other factors. Always obey traffic laws and stay attentive to the road. See your owner’s manual for system details and limitations.
‖ This information is provided for general educational purposes only and does not constitute legal advice. Warranty coverage depends on the specific terms of your vehicle’s warranty agreement. Consult your owner’s manual or a qualified legal professional for guidance on your individual situation.
