GMC Denali XT Concept (2008)

Inside, the Denali XT blends mechanical functionality with leather-trimmed comfort.

Billet-metal surrounds, controls and instruments convey the cold precision of an aircraft cockpit. This is balanced by the warmth of bespoke saddle-leather trimmed seats and other contact surfaces.

"The form language is smooth and structured to characterize GMC's power. The details have a deliberately contrasting mechanical aesthetic to mark GMC's engineering sophistication," said Warrack Leach, lead designer.

The interior features innovative instrumentation with "floating" red-illuminated numerals backed by surface chaplets in the clusters and a large integrated vehicle interface screen. The interior illumination was supplied by Osram.

The Denali XT seats four. The high-cowl vehicle architecture enables higher seating positions, allowing the couple distance between front and rear occupants to be reduced without compromising knee room. This packaging efficiency creates generous interior and cargo bed dimensions within a more compact package.

Truck capability

With stiffness that is greater than most conventional, body-on-frame trucks, the Denali XT's unibody structure supports a very capable truck platform. It also serves as the mounting point for a four-wheel independent suspension that gives the vehicle its performance feel on the road. The multilink front suspension features a forward-mounted steering rack and dual lower links with ball joints at the outer ends, providing sharp responses to driver input. At the rear, a four-link suspension design uses coil-over shocks and a decoupled stabilizer bar to enhance cornering control, reduce body roll and optimize longitudinal compliance. In short, it's a truck that hauls more than cargo on twisting roads.

The rear cargo area is wide, deep and flat, with no suspension or wheelhouse protrusions; the cargo floor measures 55 inches long (1,397 mm) by 47.5 inches wide (1,206 mm). It all adds up to the space to haul a wide variety of lifestyle accessories.

The easy-to-operate Midgate can be lowered to extend the cargo-carrying capacity inside the vehicle. The rear seats fold flat to provide a longer floor for carrying items such as skis, surfboards or wood from the home improvement store. A fixed rear window allowed engineers to retain the vehicle's structure, reducing mass and complexity.

The Denali XT has an estimated payload capacity of 1,100 pounds (499 kg) and a towing capacity of an estimated 3,500 pounds (1,587 kg). This capability is delivered through unique vehicle and powertrain integration, where the multiple modes of GM's two-mode hybrid system provide towing capability.

New 4.9L SIDI V-8 and two-mode hybrid system

For the first time, GM's rear-wheel-drive two-mode hybrid transmission is paired with a smaller-displacement version of the small-block engine. The new V-8 4.9L E85-capable engine powers the Denali XT with an estimated 326 horsepower (243 kW). It uses direct-injection technology to produce the power of a larger engine, but consumes less fuel and produces lower emissions.

Also, the functionality of GM's Active Fuel Management system has been expanded through the use of hybrid technologies, enhancing the cylinder-deactivating feature to further improve fuel efficiency.

The Denali XT's two-mode hybrid system is partnered with the 4.9L engine and uses an electrically variable transmission to enhance fuel efficiency in city and highway driving. In city driving, all-electric propulsion is used at low speeds; on the highway, fixed-gear operation enables efficient performance even when towing a trailer.

The specific characteristics of the Denali XT allowed the synergistic evolution of GM's small-block V-8 and two-mode hybrid beyond the recently introduced in GM two-mode hybrid products, such as the GMC Yukon Hybrid and Sierra Hybrid. During this optimization process, additional powertrain technologies have been integrated, including Active Thermal Management, which transfers thermal energy from one driveline component to another to improve efficiency; and a high-efficiency axle configuration, which fundamentally reduces the losses normally associated with conventional axle configurations.

The integration of the advanced internal combustion engine technologies and two-mode hybrid system on the Denali XT reinforces GMC's Professional Grade position as a brand that continues to exceed customer expectations.