Responsive and refined in almost all its various shapes and sizes, the 2012 GMC Sierra still compares well to newer full-size pickups for ride and steering and especially, for its acceleration.
GMC has four gas-powered engines and a gas-electric Hybrid on offer with the Sierra, and the two lower-displacement options are meant mostly for fleet buyers. There's a 4.3-liter V-6 with 195 horsepower, and it's really for contractors and those on very tight budgets, as its fuel economy isn't great--a four-speed automatic is the sole transmission offered, and it strains to extract power from the six. There's also a flex-fuel 4.8-liter V-8 with 302 horsepower, but it also is meant for fleet use, and disappoints on fuel economy since it shares the four-speed automatic.
The engine we'd recommend to most Sierra buyers is one of the best sellers, a flex-fuel-capable 5.3-liter V-8 with 315 hp and cylinder deactivation. Standard in the fuel-saving XFE models and optional on other Sierras, this engine delivers a ripe exhaust note, smart acceleration and the best non-hybrid fuel economy of the lineup. It pairs with a six-speed automatic that shifts pretty smoothly, and helps it get that improved fuel economy while cutting down on noise.
At the top of the range, there's a 6.2-liter, 403-hp V-8 that can run on E85. It's identical to the V-8 found in the Cadillac Escalade, but this engine delivers sports-sedan acceleration when it's in an unladen truck, and very low gas mileage all of the time. For heavy, regular towing, it's probably the best choice.
The Sierra Hybrid earns special mention here because of its vastly more complex drivetrain. The combination pairs a 6.0-liter V-8 with cylinder deactivation to an electrically variable transmission (EVT) with two electric motor/generators, four fixed-ratio gears, and a 300-volt nickel-metal-hydride battery pack. In all, the drivetrain pieces generate the equivalent of 332 horsepower and 367 pound-feet of torque, which gives the Hybrid acceleration pretty close to that of models outfitted with the 5.3-liter V-8 engine. A key difference: eerily smooth and quiet acceleration on battery power alone, up to about 25 mph.The Sierra can be had with either rear- or four-wheel drive; a single-range transfer case is standard on base versions, while dual-range 4WD is an option. An "Autotrac" electronically controlled four-wheel-drive system is featured on Denali models.
The Sierra matches its competitive 10,700-pound towing rating and payload numbers with quick, almost carlike steering and well-sorted handling. It's one of the easiest full-size pickups to drive quickly: it has communicative steering that's better than most other full-size pickups, though the Ford F-150's new electronic power steering sets a new high-water mark among trucks. Body lean is a given in any truck, but the Sierra manages it well, while providing a ride that's not jouncy or brittle, except possibly in the most extreme off-road versions. With its electric steering and regenerative brakes, the Sierra Hybrid feels more detached and the brakes are more spongy than on other models, but it's nothing that can't be mastered over time.