With such a broad range of refined and responsive powertrains, there's an engine choice for any buyer in the 2010 Sierra lineup.
The lineup starts with the base 195-horsepower, 4.3-liter V-6 installed in workhorse models. A flexible-fuel, 302-hp 4.8-liter V-8 is the first optional engine. There's also a flex-fuel 5.3-liter V-8 with 315 hp and cylinder deactivation for improved fuel economy, which is standard in XFE models and available in other versions. The most expensive Sierra pickups get a 6.2-liter, 403-hp, flex-fuel V-8 that also shows up in the swank Cadillac Escalade. Edmunds contends "acceleration is certainly acceptable with either the 4.8- or 5.3-liter V8," while the "optional 6.0-liter V-8 can get the truck to 60 mph in 7.9 seconds." The 5.3-liter is TheCarConnection.com editors' pick, as it has plenty of power for most needs without much lower fuel economy than the base V-6. Cars.com reports "the 5.3-liter V-8 is also a gutsy performer that doesn't feel taxed in the least moving the 5,326-pound Sierra crew cab...[and] also emits a pleasing V-8 rumble."
The base V-6 and base V-8 are teamed with a four-speed automatic; all other versions have a six-speed automatic that shifts very smoothly, helps achieve better fuel economy, and cuts down on noise. Cars.com says the transmission "will kick down quickly if you need to pass." ConsumerGuide confirms the "smooth-shifting transmission kicks down quickly for more passing power." The Sierra gets up to 15/22 mpg in the XFE edition, falling to only 12/19 mpg in loaded versions. Edmunds says that while these figures are "hardly impressive," the 5.3-liter engine is "the most efficient V-8 available in a mainstream full-size truck."
The lineup also is offered with either rear- or four-wheel drive-a single-range transfer case is standard this year, while dual-range 4WD is an option-or with electronically controlled four-wheel drive on the most expensive versions. The latter Autotrac system "features an automatic setting that shifts into 4WD when wheel slippage is detected," according to Edmunds.
The Sierra's powertrains perform well, but the truck shines in combining competitive towing and hauling numbers with uncharacteristically sharp steering and handling. The Sierra is one of the easiest full-size pickups to drive, with more communicative steering than other full-size pickups. Edmunds provides the overall assessment that the Sierra is "a very comfortable and easy truck to drive," though it can be "hampered by a slightly larger turning circle than most other trucks." Kelley Blue Book finds it "surprisingly nimble and easy to maneuver." ConsumerGuide observes "noticeable body lean in fast turns and quick changes of direction" but acknowledges "steering is nicely weighted, if a bit numb." Cars.com says, "with an unladen cargo bed, the Sierra's ride quality is fairly stiff, but the suspension does a good job soaking up large imperfections in the road."
While it handles crisply, the Sierra also can tow 10,700 pounds when equipped with an optional package. That's only 600 pounds short of the class leader, the rugged Ford F-150.
All the performance characteristics change in the GMC Sierra Hybrid except handling. The Hybrid's powertrain combines an aluminum 6.0-liter V-8 with variable valve timing and cylinder deactivation, to which GM adds an electrically variable transmission (EVT) with two electric motor/generators, four fixed-ratio gears, and a 300-volt nickel-metal-hydride battery pack. The complex package creates 332 horsepower and 367 pound-feet of torque, which ends up feeling a lot like the Sierra's stock 5.3-liter V-8 engine, except for an eerily smooth and quiet acceleration on battery power alone, up to about 25 mph. Automobile reports "this truck accelerates to sixty mph in 9.7 seconds and through the quarter-mile in 17.3 seconds at 85 mph." ConsumerGuide remarks that the GMC Sierra Hybrid "accelerates from a stop and passes much like a conventional model," while only "a faint surge is felt and heard when it shifts between full electric and gasoline operation."
Handling's a bit digital, but reasonable. Car and Driver reports that "the steering is now electrically boosted and the brakes are of the regenerative type, a setup that offers less pedal travel and a mushy, spongy feel. These traits are definitely noticeable, but were you to buy one of these trucks, we think you'd get used to them rather quickly." According to MotherProof, the 2010 GMC Sierra Hybrid also features "regenerative braking to capture energy from braking and coasting and store it in the battery for future use." The Sierra Hybrid's powerful brakes also recharge its batteries, and though it's a few hundred pounds heavier than the V-8 truck, the Sierra Hybrid handles well (ConsumerGuide praises the "comfortable, compliant ride" and notes "there's less reverberation over bumps than in most pickups") and can tow up to 6,100 pounds in rear-drive form-and can go lean on fuel for an EPA-rated 21/22 mpg (20/20 mpg with 4WD). Cars.com calculates that "two-wheel-drive models have a cruising range of more than 500 miles between fill-ups."