Silverado Hybrid hauls with best

While other car companies have dutifully put gasoline-electric hybrid power into relatively modest-size cars, General Motors had a different idea: Put the fuel-saving technology into some of the biggest passenger vehicles, including its best-seller, the Chevrolet Silverado pickup.

Not even GM's financial struggles and approaching bankruptcy could prevent the debut early this year of the 2009 Chevrolet Silverado Hybrid, the nation's first full hybrid full-size pickup.

It differs from earlier Silverado Hybrids because it can travel on electric power at up to 30 mph. Earlier Silverado Hybrids did not have this so-called two-mode hybrid system.

This is no wimpy pickup. It comes only as a four-door crew cab with 53/4-foot-long bed, so it's 19.2 feet long from bumper to bumper. Its V-8 can tow up to 6,100 pounds, and its top payload rating is 1,459 pounds.

Still, with a fuel economy rating as high as 21 mpg for city driving and 22 mpg on the highway for a two-wheel-drive model, the hybrid is tops in fuel mileage among all pickups except for the Ford Ranger and Mazda B2300 compacts with four-cylinder engines.

Indeed, the hybrid, with city fuel mileage that's 40 percent better than a regular, gas-only Silverado, can travel about 500 miles on a tank of fuel, according to the government's fuel mileage estimate.

It's too bad, then, that the Silverado Hybrid is so pricey, even after factoring in the federal government's $2,200 tax credit. The starting price is $39,015 for a two-wheel-drive model and $42,165 for all-wheel drive.

This compares with $30,050 and $33,200, respectively, for two- and four-wheel-drive base Silverado crew cabs that run on gasoline only.

The mileage estimates for the gasoline Silverado are no better than 15/21 mpg. Even so, it would take years for a buyer to recoup the premium price of the hybrid, even considering the $2,200 tax credit that comes with it.

Sure, surveys show that consumers are more attuned to the environment, but with the economic doldrums, it remains to be seen how this newest Silverado pencils out financially for most truck buyers.

At stoplights, the gasoline engine turns off and stays in silent "Auto Stop" mode until the driver needs to move again.

Then, the truck can propel forward in silence slowly up to about 30 mph as electric power alone moves the 5,600-pound-plus vehicle if the driver works the throttle gently.

As speed picks up, the gas engine starts up. The Silverado uses the same 6-liter, overhead valve Vortec V-8 that's used in the Chevy Tahoe Hybrid sport utility vehicle.

In the Silverado, the engine generates 332 horsepower and peak torque of 367 foot-pounds at 4,100 rpm. It works to get everything it can from its fuel through an economical Atkinson cycle and GM's Active Fuel Management system, which deactivates some cylinders during coasting and other driving conditions.

Power is delivered to the wheels by an electrically variable transmission with four gears and mostly smooth operation. I did notice, however, a brief stumble or hesitation when the engine switched from pure electric power to gasoline power.

It's similar to what a driver can experience if an engine is about to stall, and it's not uncommon in gas-electric hybrid powerplants where software controls the mixing and matching of power flows. Still, in the test truck it was a regular reminder that this wasn't a normal pickup.

So were the dirty looks I got from people walking in parking lots. They'd look behind and find this big truck creeping behind them silently.

Braking was different, too. Brakes had a distinctly artificial feel. Try as I might to stop smoothly, they would grab right at the end of the stop, so even at slow speed, there was an abruptness to any stop.

The brakes are regenerative, meaning they seek to capture energy as the vehicle slows and store it in a 300-volt battery storage system for use later by the hybrid system's two electric motors.

I drove the all-wheel-drive Silverado Hybrid as normally as possible, carrying furniture and people. My mileage rating was 16 mpg combined city/highway, compared with the government's 20/20 mpg rating.

There was a truckish bounce over severe bumps and highway expansion cracks. The truck bobbed up and down on some concrete pavement.

Steering was comfortable, and there was good space inside for all passengers. There was tire noise in the passenger compartment. I also heard the V-8 during fast passing on the highway.