2005 GMC Graphyte Concept

As with any serious SUV, the Graphyte features ground-gripping permanent all-wheel drive, delivered through the Two Mode's

The Graphyte features ground-gripping permanent all-wheel drive, delivered through the Two Mode's unique drivetrain system. (Photo: Trevor Hofmann, Canadian Auto Press)

unique drivetrain system. An electronically-controlled series of gears and two electric motors act as the gateway for power which travels to each of the four wheels. Remarkably, these components have been compacted and enclosed in a gutted Hydramatic 4L60-E automatic transmission case, a staple transmission for GMC trucks and SUVs.

A 300-volt nickel-metal hydride (NiMH) battery is the main power source for the hybrid and electrical components in the Graphyte. The main, large-format cell is hidden away beneath the rear passenger seat, while a separate pack, located under the hood, provides power for the accessory systems, such as HVAC, power steering and power brakes.

The clever placement of the battery cells demonstrates that they don't necessarily need to be integrated into the frame

At speed, the Graphyte automatically lowers its ride height to improve aerodynamics and fuel consumption. (Photo: Trevor Hofmann, Canadian Auto Press)

or sandwiched in the chassis, which reduces overall production and engineering costs.

The Graphyte is of traditional body-on-frame design, praised by off-roaders for its greater durability and towing strength, but live axles, typically found on trucks, won't be found here. An advanced, electronically adjustable suspension which consists of struts in front and a five-link layout in back is used instead.

At speed, the vehicle automatically lowers its ride height to improve aerodynamics and fuel consumption, but the suspension can also be raised to increase ground clearance when off-roading.