GM Hybrid-Pickup Engineering Meets Expectations; Attracting Buyers Another Matter

SAN ANTONIO – They say everything is bigger in Texas. Now add hybrids to the list, with the launch of the ’09 Chevrolet Silverado/GMC Sierra 2-Mode Hybrid pickup.

The nation’s second-largest pickup market behind California starts seeing the trucks at dealerships now, as does the rest of the U.S. for that matter, but they arrive everywhere during a record-weak economy, inexpensive gasoline and a nightmarishly low new-vehicle sales environment.

In short, it appears the timing could not be worse for an expensive, niche product like the Silverado/Sierra hybrid. Or maybe not.

General Motors Corp. says everyday consumers never were the primary target of the pickups. Instead, the auto maker believes fleet owners operating in a predominantly urban environment will comprise its core consumers, and President Obama just signed an $800 billion stimulus bill with lots of money going to infrastructure improvements.

Those worksites certainly will need the brawn of a fullsize pickup, and the 40% gain in city fuel economy the trucks deliver is a cost savings worthy of a project manager’s consideration.

The trucks also carry a $2,500 tax credit, which helps defray the $3,000 premium GM’s hybrid system adds to their $38,995 base sticker price. Talk in Washington hints of even greater consumer incentives toward the purchase of alternative-propulsion vehicles.

Also, environmentalism will never go out of style, regardless of which direction the economy might head. Those folks with deeper pockets might get a charge out of the 2-mode system’s whiz-bang technology, as well as the fact they’ll have the only hybrid pickup on the road today.

Here’s how the system works. Two sources of power move the truck – a standard 6.0L OHV V-8 and a pair of electric motors inside its electrically variable transmission. Power goes to the electric motors via a 300-volt nickel-metal-hydride battery pack under the crew cab’s rear bench seat, which unfortunately nixes some storage space.

GM’s cylinder-deactivation system shuts down to 4-cyl. operation whenever possible, and other technologies, such as late intake-valve closing and stop/start capability, further improve efficiency.

The motors in the transmission also work to recharge the battery when the vehicle is coasting, and regenerative braking recaptures energy lost during the braking process. A 300-volt air-conditioning compressor and electric heater pump maintain passenger comfort during prolonged stops.

So perhaps the biggest hurdle these hybrids face in drawing consumers is the 4,000 lbs. (1,814 kg) or so of towing capability they sacrifice to conventionally powered models. However, at a media preview here, the trucks flexed their muscles as easily as their old-fashioned counterparts.

With a towing capacity of 6,100 lbs. (2,767 kg), the Silverado/Sierra hybrid made short work of hauling a horse trailer weighted to 5,100 lbs. (2,313 kg) with sand bags and a 23-ft. (7-m) Sea Ray power boat tipping the scales at 5,300 lbs. (2,404 kg). The hybrid pickup’s tow rating aside, many ranchers still may prefer to haul their horses with the much more powerful diesel-powered, medium-duty Silverado dually pickup.

The instant torque of the transmission’s electric motors means the hybrid pickups don’t exhibit that decision-making hesitation some conventional trucks take from a standing start.

Most interesting is the hybrid pickup doesn’t need assistance from its 6.0L gasoline engine at takeoff. The ICE kicks in before eclipsing 10 mph (16 km/h) during towing loops, but its ability to get rolling under battery power alone speaks to the toughness of GM’s 2-mode system.

Without pulling a load, GM claims the electric motors propel the trucks up to 30 mph (48 km/h), according to GM, before the ICE takes over.

This seems a bit of a stretch. A full day behind the wheel with plenty of chances to baby the pickups from a dead stop never yielded 30 mph under battery power alone. Somewhere just above 10 mph (16km/h) was the norm, consistent with previous testing we conducted early last year with the GM fullsize SUVs with the 2-mode system.

Compared with 2-mode SUVs, though, GM has made tremendous strides with the regenerative braking. Engineers tweaked the system not so much to recapture more energy but to iron out the “grabbiness.” Pedal feel is no different than a fullsize truck equipped with conventional brakes.

GM engineers also enhanced the cylinder deactivation system so the pickups stay in 4-cyl. mode longer. But one modification everyday drivers will appreciate most is the addition of hydraulic body mounts that tame the freeway hop often plaguing pickups at higher speeds.

GM engineers used a notorious stretch of Highway 101 in Southern California between Oxnard and Los Angles to prove the new mounts, and their real-world testing reveals itself through an uncharacteristically smooth ride. The mounts appear on all ’09 GM pickups.

But the bottom lineis fuel economy, and GM says the hybrid truck will achieve 21-22 mpg city/highway (11.2-10.7 L/100 km) with 2-wheel drive and 20/20 mpg (11.8 L/100/km) with 4-wheel drive. Compared with a conventional fullsize Silverado/Sierra, the trucks get 40% better fuel economy in the city cycle and a 25% improvement overall.

During testing through the heart of urban San Antonio, we averaged 18 mpg (13.1 L/100 km), which again falls in line with our previous experience in GM’s 2-mode SUVs and also comes up short of GM’s estimates. But 18 mpg in the city with a fullsize truck packing V-8 work credentials is nothing to sneeze at. Spread over a fleet of trucks it could amount to considerable fuel savings. Of course, mileage will suffer when the truck is loaded with tools and materials.

In the end, the trick to getting the greatest operating efficiency out these hybrids is no different than a conventionally propelled vehicle – avoid jack-rabbit starts and anticipate stops instead of jamming on the brakes at the last minute.

Sensible use of the accelerator and brake will keep the needle of the truck’s instrument-panel-mounted efficiency gauge pointing straight up and within the powertrain’s operating sweet spot.

In addition to the efficiency gauge, the human-machine interface includes an energy flow display screen dedicated to split-second workings of the powertrian to further assist drivers in achieving maximum efficiency.

On the design front, the hybrids retain the good looks of their conventionally propelled stablemates both inside and out, with special badging the only difference. These are not stripper trucks, either, so expect items such as Bluetooth, 18-in. polished wheels, leather-wrapped steering wheel and MP3-capable sound system.

But will they sell? GM marketers think so, citing the expectation for a comeback among commercial customers and pent-up demand among regular folks towing and hauling on the weekends and then using their pickups as a daily driver during the week.

We’ll see soon enough. But in a turn of events here so ironic it almost seemed contrived, a driver of a late-model GMC Sierra pulls up to the GM testing site and asks about the fuel economy figures on the hybrids. After a short chat with GM officials, the driver tucks a hybrid Monroni in his pocket and says in a Texas drawl, “Thanks, my boss needs 30 of ’em.”