2005 Chevy Silverado Hybrid Preview

"These hybrid pickups will save more fuel than gasoline-powered pickup trucks, with no compromise in performance or

In the hybrid truck, GM replaces the conventional electric starter and alternator with a compact electric motor. (Photo: General Motors of Canada)

utility. In addition, Miami-Dade [and all those that purchase a Silverado HEV] will now have the flexibility and productivity of generating wall-quality electrical power from the GM pickup truck when in remote locations," commented John Gaydash, GM Fleet and Commercial marketing director.

How does it work? GM replaces the conventional electric starter and alternator with a compact electric motor, itself integrated between the engine and transmission in a patented, space-efficient manner. Unfortunately there isn't any added torque provided by the electric motor to help out when towing heavy loads, but nevertheless the electric motor does supply power to the transmission that in-turn delivers torque smoothing to the drivetrain. Up to 14,000 watts of continuous electric power is generated.

Those used to the regular rumble of a big V8 at idle, or an even louder diesel, will find the hybrid a bit of a shock

GM hybrid pickups take advantage of regenerative braking, which uses the kinetic energy developed by braking to recharge the batteries. (Photo: General Motors of Canada)

when the engine stops running when the truck is stationary. Releasing the brake pedal will immediately spark the V8 engine to life and full power is restored.

Unlike Toyota's full-hybrid technology, also adapted by Ford and soon Nissan, the Silverado and Sierra trucks make use of a less sophisticated partial or mild-hybrid system - much the same as used by Honda. The jury is out as to which is better over the long haul, but partial systems are not considered quite as efficient as full-hybrid systems, as the gasoline engine needs to be running while under way - unless coasting. Full-hybrid systems can drive on electric power alone, until the batteries need recharging at which time the gasoline engine restarts.