The toughest jobs have a long list of demands and the 2025 GMC Sierra Heavy Duty trucks—the Sierra 2500 HD and Sierra 3500 HD are engineered for the hardest jobs. Sporting a clean design, the Sierra HD trucks are masterfully crafted to be workhorses with equal parts durability, power and luxury. Tow, haul, and perform with incredible force. With a staggering amount of customization available choose your cabin size, standard, crew or double cab, and get the right bed size to match with a standard and long bed available. Explore the 2025 Sierra HD truck with your automotive leader right here in Ontario, Gus Brown Port Perry. Let our experts take you through a tour of these true heavy-duty truck titans.
2025 Sierra HD Exterior
Rugged, Yet Luxurious Design
Ready to dominate the worksite and whatever challenges await, explore the updated exterior of the 2025 GMC Sierra HD trucks. Crafted to be functional, yet modern, the Sierra HD will make an impression.
- New Wheels: Sierra HD sports a bold look with new available 20” wheels with bright face and dark-painted pockets.
- Exterior Lighting: Light the road ahead in the Sierra HD, with new LED projector headlamps with unique animated sequences.
GMC PRO Multigate
Featuring six unique functions to help assist you with loading and unloading the cargo box, the world’s first-ever six-function MultiPro Tailgate is an innovative detail that is hard to refuse. The MultiPro Tailgate features:
- Primary Gate: Open with either your key fob’s power release or directly from the button on the gate.
- Primary Gate Load Stop: Your load stop can help prevent items from sliding out of your bed while you have your gate open.
- Easy Access: The inner gate can fold down to give you easy access while loading and unloading the cargo bed.
- Full-Width Step: Remove the conventional hitch to turn the inner gate into a step for easy entry and access to the cargo bed.
- Inner Gate Load Stop: The inner gate’s load stop helps to prevent second-tier items from sliding out of the cargo bed.
- Inner Gate With Work Surface: Turn the opened inner gate into a convenient working surface in a pinch.
Best-In-Class HD Cargo Bed Volume
Offering top-tier storage for all your equipment and gear while you’re on the job, Sierra HD offers best-in-class HD Cargo Bed Volume. Bring all your equipment while you’re on the clock and don’t stress about being short on space.
2025 Sierra HD Interior
First-Class Comfort
Outfitted to provide the highest level of comfort and utility, get comfortable in the interior of the 2025 Sierra HD. Stretch out with your passengers while you experience the best-in-class rated Crew Cab front headroom and legroom. Drivers will also lounge in luxury thanks to the available best-in-class 16-way power front seats with massaging feature.
Interior Amenities
The 2025 Sierra HD features numerous amenities, treating you and your passengers on every journey. Features include, dual-zone climate control, heated steering wheel, available all-weather floor liners with removable carpet inserts, and more.
Trim Unique Interiors
Discover a world of luxurious materials and eye-catching colours with unique interiors across trim levels. Gorgeous leathers, woods, and other metals can be found within the cabin of the Sierra HD. Interiors include:
- Jet Black, Cloth Seat Trim (Pro/SLE)
- Jet Black, Vinyl seat trim (Pro)
- Dark Walnut/Slate, Cloth seat trim (SLE)
- Jet Black, Perforated Leather-appointed front outboard seating positions (SLT)
- Dark Walnut/Slate, Perforated Leather-appointed front outboard seating positions (SLT)
- Jet Black with Kalahari accents, Perforated Front Leather seat trim (AT4)
- Jet Black, Forge Perforated Leather seat trim (Denali)
- Atmosphere/Brownstone, Forge Perforated Leather seat trim (Denali)
- Obsidian Rush, Full Grain Leather seat trim (AT4X)
- Alpine Umber, Full Grain Leather seat trim (Denali Ultimate)
2025 Sierra HD Image Gallery





Performance & Capability
Performance
Engineered to perform first and foremost, the 2025 Sierra HD makes your day on the job that much easier. With up to 36,0000 lbs of max-towing power available, and innovative features that are exclusive to top trim levels like the Denali and AT4, you can demand more out of your truck and have the Sierra HD fulfill all expectations.
Diesel Power
Diesel enthusiasts will rejoice with the 6.6L Duramax Turbo-Diesel V8. Featuring an efficient turbocharger, the Sierra HD provides superior low end torque compared to the competition.
2025 Sierra HD Engine & Transmission Options
Specifications | Sierra 2500 | Sierra 3500 |
Engine | 6.6L V8 Gas Engine / 6.6L Duramax Turbo-Diesel V8 | 6.6L V8 Gas Engine / 6.6L Duramax Turbo-Diesel V8 |
Horsepower | 401 hp / 470 hp | 401 hp / 470 hp |
Torque | 464 lb-ft / 975 lb-ft | 464 lb-ft / 975 lb-ft |
Max Payload | 1805 kg (3,979lbs) | 3376 kg (7,442 lbs) |
Technology
Pro Grade Trailering System
Trailer with confidence in the 2025 Sierra HD. The Sierra HD offers the most trailering technologies in its class, as you tow and haul with ease. Explore the available ProGrade Trailering System. These intelligent trailering technologies make hitching and towing go as smoothly as possible. Features include:
- Temperature Monitor
- Trailer Side Blind Zone Alert
- Diesel Exhaust Brake
- Adaptive Cruise Control with Trailering Trailer Sway Control
- Trailer Length Indicator
- Trailer Brake Controller
- Trailer Angle Indicator with Jack-Knife Alert
- Gross Combined Weight (GCW) Alert
- Trailer Light Test
- Trailer Theft Detection
- Smart Trailer Integration with the Available myGMC Mobile App
- Maintenance Reminders
- Auto Electric Parking Brake
- Create and Customize Trailer Profiles
- Tow/Haul Mode Reminder
- Predeparture Checklists
- Available myGMC Mobile App† with Trailering
- Tow/Haul Mode
- Trailering Mirrors
Up to 14 Available Camera Views
Keep tabs on your truck, trailer and all of your surroundings with up to 14 different available camera views on the 2025 GMC Sierra HD. Drivers can experience the HD Surround Vision system, Enhanced Transparent Trailer View, Rear Camera Mirror, Bed View Camera, Rear Trailer View, Forward and Reverse Side View Bias, and so much more.
Class Leading 13.4” Diagonal Centre Touchscreen
Explore the available 13.4″ diagonal touch-screen for a premium infotainment experience. Fully customizable and the largest in its class, drivers can connect wireless Apple Carplay and Android Auto, explore navigation, music and more.
Safety
Sierra HD Pro Safety
Piloting a HD truck takes skill, thankfully GMC has a comprehensive suite of driver assists and safety technology to keep you confident and safe while you’re behind the wheel. Highlighted technologies include:
Available Lane Keep Assist with Lane Departure Warning: this system alerts the driver when they may be accidentally drifting out of their lane, keeping the driver on a steady course. This system will not activate when the driver is intentionally changing lanes or has their signal light on.
Available Front and Rear Park Assist: Providing distances between walls, curbs, vehicles, and other objects while parking, this assist will help you pull into and back out of parking spaces with ease.
Other highlighted available advanced safety features include:
- Rear Cross Traffic Alert
- Intellibeam—Auto High Beams
- Safety Alert Seat
- Forward Collision Alert
- Following Distance Indicator
- Front Pedestrian Braking
- Hitch Guidance
- Hitch Guidance with Hitch View
- Adaptive Cruise Control
- Lane Departure Warning
- Lane Change Alert with Side Blind Zone Alert
- Buckle to Drive
- Automatic Emergency Braking
What’s New For Sierra HD in 2025?
The Sierra HD receives minimal updates for 2025, with slight shuffling of standard features across trim levels. The Sierra HD was brand new for the 2024 model year and received vast updates. Highlights of the new model generation included: a reworked front fascia and exterior lighting, the addition of new driving technology, specifically improving trailering tech, and a reworked Duramax Turbo Diesel V8.
2025 Sierra HD Models
Get to work in the 2025 GMC Sierra HD available at Gus Brown in Port Perry. Whether you’re looking for a new HD truck, half-ton pickup, or want to get into an SUV, our experts have you covered. Explore our GMC and Buick models available in our new and used inventories. Shop for genuine OEM parts, tires, schedule service with our team, and more. Visit our dealership today, or contact us now to get started.