2007 GMC Sierra 3500HD III (GMT900) Regular Cab Long Box Dimensions, Size & Specs

The curb weight of this GMC Sierra 3500HD III Regular Cab Long Box ranges from 2564 kg to 3062 kg (5654 to 6752 lbs), which reflects the vehicle's bare operating weight including fluids and standard equipment. The maximum weight capacity it can handle goes up to between 4309 kg and 5171 kg (9497 to 11400 lbs), indicating its impressive payload and towing capability. Such heavy-duty specs mean the truck is ideal for demanding commercial or personal hauling tasks, delivering stability and strength even under substantial load, which impacts fuel efficiency and handling but is essential for robust work performance.

The ride height or ground clearance of the 2007 GMC Sierra 3500HD III Regular Cab Long Box is 233 mm (9.2 inches). This ground clearance allows the truck to navigate rough terrains, obstacles, and uneven surfaces more easily, making it highly suitable for off-road conditions or construction environments. Adequate ground clearance helps to prevent damage to the underside of the vehicle and ensures better approach, breakover, and departure angles, all of which contribute to greater versatility and capability in challenging driving situations.

The 2007 GMC Sierra 3500HD III Regular Cab Long Box offers a significant rear cargo capacity of 2170 liters (approximately 76.6 cubic feet) with the rear seats folded. This volume is especially valuable for accommodating large or bulky items, reflecting the truck's utility focus. Such capacity allows users to transport construction materials, large equipment, or recreational gear easily. This makes the vehicle practical not only as a heavy-duty work truck but also for activities that require extensive cargo space.

The 2007 GMC Sierra 3500HD III Regular Cab Long Box comes equipped with several tire and rim size options to suit various performance needs and terrains. Rim sizes include 6.5J x 17, 7J x 16, and 7.5J x 17, while tire sizes available for this model are 265/75 R16, 265/70 R17, and 225/75 R17. These sizes offer a balance between road comfort, off-road capability, and load capacity. Selecting the appropriate tire and rim size is crucial for maintaining vehicle stability, traction, and overall durability under demanding conditions.

Fitting the 2007 GMC Sierra 3500HD III Regular Cab Long Box into a standard residential garage can be challenging due to its substantial size. The truck's length is 5714 mm (224.9 inches) and its width with mirrors extended is 2436 mm (95.9 inches). In many cases, a standard garage door is approximately 2440 mm (96 inches) wide, and typical garage length is around 5486 mm (216 inches or 18 feet). Consequently, this truck might be too long for some garages and very tight width-wise, particularly with mirrors extended, requiring careful measurement before attempting to park inside. Owners might need to fold mirrors or have a larger garage to accommodate it comfortably.

Compared to its predecessor, the GMC Sierra 3500HD III (GMT900) Regular Cab Long Box introduced in the early 2000s, the 2007 model generally features an increased overall length, slightly wider stance with mirrors, and an improved payload and towing capacity. These enhancements come with minor increases in curb weight but result in better hauling performance. The newer generation expanded main dimensions to accommodate more powerful drivetrain options and enhanced suspension systems for durability. Overall, the III generation brought a more modern design and more practical heavy-duty capabilities while maintaining the ruggedness expected in this truck segment.

When compared to similar heavy-duty pickups like the Ford F-350 Super Duty or the Ram 3500 from the same era, the 2007 GMC Sierra 3500HD III Regular Cab Long Box holds its own with competitive dimensions and capabilities. It has a slightly longer body length at 5714 mm (224.9 inches) and width with mirrors at 2436 mm (95.9 inches), which is on par or slightly larger than competitors. In terms of payload and towing, it provides comparable or better capacities, making it highly functional for demanding work duties. The combination of size, ground clearance, and cargo capacity positions the Sierra 3500HD as a top contender in the heavy-duty truck market segment.

The 2007 GMC Sierra 3500HD III Regular Cab Long Box features a single-row seating configuration typical for regular cab trucks, focusing more on driver and passenger space rather than rear passenger capacity. This configuration prioritizes maximizing bed length and cargo volume in the long box design. While the interior is utilitarian to suit work truck needs, it delivers sufficient comfort and ergonomics for the driver and front passenger. The rear seats are generally absent or minimal in this cab style, but the extended bed length compensates by offering greater cargo space for tools, equipment, and materials.

Between 2007 and 2010, the GMC Sierra 3500HD III Regular Cab Long Box represented the pinnacle of GMC's heavy-duty pickup offerings, designed to meet the rigorous demands of commercial and personal users requiring substantial payload and towing performance. It balanced size, strength, and versatility, embodying GMC's commitment to durable, capable trucks within its lineup. This generation emphasized enhanced powertrain options, improved driving dynamics, and increased cargo capacity, positioning it as a vital tool for industries such as construction, agriculture, and towing services, while also appealing to enthusiasts requiring serious truck functionality.