The GMC Sierra Hybrid is a powerful, full-size pickup that achieves 40-percent greater city fuel economy and a 25-percent improvement in overall fuel economy than non-hybrid models, while delivering the capability expected of a full-size truck — including a 6,100-pound towing capacity.
Partnering General Motors' patented two-mode hybrid system and a powerful 6.0L gas V-8, the Sierra Hybrid delivers highly efficient performance, including all-electric driving up to 30 mph. That saves fuel even when the truck is fully loaded or towing a trailer.
EPA-estimated fuel economy for both 2WD and 4WD models is 21 mpg in the city and 22 on the highway. With the 26-gallon fuel tank, Sierra Hybrid delivers a cruising range of more than 500 miles.
The Sierra Hybrid is offered in the Crew Cab body style on both 2WD and 4WD models. Each model is equipped with several standard, popular features, including StabiliTrak electronic stability control system, a locking rear axle and a trailering package. Sierra Hybrid also offers dual-stage frontal air bags and head curtain side air bags, and it is the only full-size truck with five-star side-impact ratings in federal crash tests.
The Sierra Hybrid's fuel-saving performance is derived from GM's advanced Electrically Variable Transmission (EVT) and 300-volt nickel-metal hydride Energy Storage System (ESS), which work with the standard 6.0L V-8 gasoline engine with Active Fuel Management (AFM) and late intake valve closing (LIVC) technology. GM's hybrid system not only enables the Sierra to launch and drive up to 30 mph on electricity alone, it allows the Vortec 6.0L V-8 engine to operate in its more economical V-4 mode for longer periods.
As part of the vehicle's emission control system, the ESS is warranted for eight years/100,000 miles.
In the Sierra Hybrid, the hybrid system itself generates the electricity used to propel the vehicle. When the brakes are applied or the vehicle is coasting, the electric motors within the hybrid system create electricity that is stored in the 300-volt battery. This stored energy moves the vehicle and the regenerative braking cycle is renewed.
The hybrid system provides seamless, dependable power on demand in an efficient package. In fact, its electric motor is less than half the size of those in single-mode hybrid systems.
This technology was developed and is still used in fleets of hybrid transit buses in more than 70 North American and European cities. Scaled down for use in passenger vehicles, the two-mode system delivers fuel savings where it is needed most — in large vehicles with high levels of capability. The system was first introduced on the 2008 Yukon Hybrid. It is a core part of GM's energy diversity efforts, centered on reducing dependence on petroleum, improving fuel economy, reducing emissions and minimizing the automobile's impact on the environment.
Integration of the hybrid system on the Sierra is seamless — the battery pack is beneath the rear seat — and delivers a quiet driving experience. Contributors to this include:
New exhaust system and resonator tuned for the 6.0L engine's Active Fuel Management operation.
Additional engine intake induction tuning for reduced interior noise and pleasing sound quality.
Low-rolling resistance, “quiet-tuned.” P265/65R18 tires for reduced road noise
Electrically driven 300-volt air conditioning compressor reduces vibration and allows the standard, tri-zone HVAC system to cool the passenger compartment even when the gasoline engine is shut off
Electrically driven 42-volt variable-assist power steering reduces vibration and provides up to a 0.5-mpg fuel economy improvement by reducing parasitic losses common in belt-driven hydraulic systems
Energy Storage System (ESS) cooling system internal fan is tuned to be quiet at low vehicle speeds.
Along with quietness, the Sierra Hybrid also delivers exceptional driving smoothness, thanks to specifically tuned shocks for its Z85 suspension and a hydraulic body mount. Located on the passenger side of the chassis, the hydraulic mount provides a dramatic improvement in highway driving smoothness, particularly on rough or choppy road surfaces.
In addition to increased fuel economy, the Sierra Hybrid's electrically variable transmission also provides tremendous trailering capability, enhancing driving smoothness and quality when towing. Towing capacity is 6,100 pounds with 2WD models and 5900 pounds with 4WD models.
Electric drive is enabled up to approximately 30 mph, saving fuel even when the truck is towing a trailer.
The EVT incorporates grade braking and tap up/tap down shift control. It also benefits towing on curves or lower-speed back roads, as exceptionally smooth gear transitions eliminate the “shift shock” torque disruption that can occur during abrupt shifts, such as when slowing or braking.