For release: Thursday, Dec. 13, 9:30 a.m. EST
Trio of New EcoTec3 Engines Powers Silverado and Sierra
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Advanced combustion system increases power and efficiency
Seamlessly switches to four-cylinder operation under light loads
Rugged hardware engineered to help keep operating costs down
New 4.3L V-6 with ample torque for towing and hauling, even in a crew cab
DETROIT – The 2014 Chevrolet Silverado 1500 and GMC Sierra 1500 will deliver more power,
more torque and improved fuel efficiency, thanks in part to a trio of all-new EcoTec3 engines
designed specifically for the needs of full-size truck customers.
The new engine family includes a 4.3L V6, a 5.3L V-8 and a 6.2L V-8.
EcoTec3 engines feature three state-of-the-art technologies – direct injection, cylinder
deactivation and continuously variable valve timing – to make the most of power, torque and
efficiency across a broad range of operating conditions.
“We believe these are the most technologically advanced engines ever offered in light-duty
pickups, and they are 100 percent truck – specifically designed for the way customers use
trucks in the real world,” said Jordan Lee, Small Block chief engineer and program manager.
“They have all the power and torque needed to confidently handle the tough jobs, and they
seamlessly switch to four-cylinder mode to increase efficiency during light-load driving.
“This is technology no other truck maker can match, and we offer it in every one of our EcoTec3
engines, for every one of our customers,” said Lee. “It is not an extra cost feature. You get our
best and most sophisticated technology regardless of trim level.”
Although they share only a handful of parts with previous Chevrolet and GMC engines, the new
EcoTec3 engines build on experience gained from millions of trucks and billions of real-world
customer miles, while incorporating the latest in advanced materials and combustion systems.
“The combination of straightforward mechanical systems, the latest in materials, and an
advanced combustion system enable us to improve power and efficiency, while also reducing
noise and vibration,” said Lee. “We think truck customers will find our new engines to be the
right tools for the toughest jobs, while helping hold down ownership costs over the long run.”
A family of three all-new engines
The EcoTec3 lineup for the 2014 Silverado and Sierra 1500 includes a 4.3L V-6 and 5.3L and
6.2L V-8s, all matched with proven, efficient six-speed transmissions in the United States and
Canada.
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The new 4.3L V-6 will offer budget-conscious customers a state-of-the art truck engine,
with ample torque to power a crew cab and tow a trailer.
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The new 5.3L V-8 is engineered for more horsepower, more torque and better fuel
economy than the current 5.3L V-8.
The new 6.2L V-8 is expected to be the most capable engine offered in any light-duty
pickup truck.
SAE certified horsepower and torque ratings and EPA fuel economy estimates for the new
Silverado and Sierra will be available beginning early next year.
Advance combustion system drives greater power, efficiency
At the heart of the new EcoTec3 engine family is an advanced combustion system that
maximizes the potential of the direct fuel injection system, cylinder deactivation, continuously
variable valve timing and other technologies.
Development of this advanced combustion system involved extensive design and engineering
by GM’s global powertrain organization. More than 100 iterations of the combustion systems
were evaluated through computer modeling before a final design was selected for each engine
variant. The overall engine design involved more than 10 million hours of computational CPU
time, with the combustion process alone accounting for more than 6 million of those CPU hours.
“Owning a truck doesn’t mean settling for second-best technology,” said Lee. “Our new
EcoTec3 engines harness some of the most advanced powertrain technologies in the world to
meet the specialized demands of truck owners.”
For example, truck engines often need to provide maximum power under heavy load for long
periods of time, such as towing a trailer up a mountain grade or slogging through mud at a job
site. A rugged, large displacement engine is well suited to reliably providing this power and
torque, year in and year out.
“For the 2014 Silverado and Sierra 1500s, these larger displacement EcoTec3 engines can now
instantly switch to four-cylinder mode to improve efficiency when less power is required. It gives
customers the best of both worlds – a rugged truck engine when they need it, with improved
efficiency in light-load driving,” said Lee.
The ability to more precisely control combustion also enables the new engines to run with a
higher compression ratio – 11.0:1 for the versions with regular fuel recommended. This higher
compression is one of the best ways to simultaneously increases both power and efficiency.
This increased efficiency can now be maintained over a broader range of operating conditions.
For example, when towing a trailer on a hot summer day, Silverado and Sierra’s advanced
combustion system can reduce the need to trim back spark advance to control detonation,
helping maintain both performance and real-world fuel efficiency, even when the going gets
really tough.
Emissions are also reduced, particularly during cold starts, when hydrocarbon emissions are cut
by about 25 percent.
Direct injection for precise fuel metering
New EcoTec3 engines use direct fuel injection, which precisely meters fuel directly into the
cylinders, to optimize combustion over a broad range of conditions.
The engines also feature a new cylinder-head design and a new, sculpted piston to optimize the
mixing of air and fuel in the engine and the burning of the mixture to create power.
The heads features smaller combustion chambers shaped to complement the unique
topography of the piston heads. The smaller chamber size and sculpted pistons produce a
compression ratio of 11.0:1 or higher, depending on the engine, while the heads features large,
rectangular intake ports with a slight twist to enhance mixture motion.
To further enhance combustion, the intake and exhaust valve positions have been switched
from previous versions, and the valves are now slightly canted toward the cylinder centerline.
Also, the spark plug angle has been revised and the electrode is now closer to the center of the
chamber to support optimal combustion.
The pistons feature unique sculpted topography that was optimized via extensive computer
analysis to precisely direct the fuel spray for better mixing and more complete combustion. The
contours of the piston heads are machined after casting to ensure dimensional accuracy –
essential for precise control of mixture motion and the compression ratio.
Deactivating cylinders to enhance fuel economy
Cylinder deactivation, also known as Active Fuel Management, is now standard on all three
engines for the Silverado and Sierra 1500.
The new trucks make the most out of cylinder deactivation, with improved engine mounts,
electronic throttle control, adaptive exhaust systems, improved aerodynamics, low-rolling
resistance tires, and other technologies that help the engines operate in four-cylinder mode for
longer periods of time, further increasing efficiency.
“GM pioneered cylinder deactivation technology, and we consider it a great technology for
improving the efficiency of full-size trucks,” said Lee.
The system uses oil pressure, controlled by the powertrain control module, to deactivate the
lifters on selected cylinders, closing the valves for those cylinders. It deactivates four of the
cylinders on the V-8 engines and two cylinders on the V-6 under light load conditions –
operating the engines as a V-4 – and seamlessly reactivates the cylinders when the driver
demands greater power. The transition takes less than 20 milliseconds and is virtually
imperceptible.
“This is another great example of using a relatively simple mechanical system and powerful
software to provide a real benefit to our customers,” said Lee.
2014 Silverado and Sierra EcoTec3 engines features and highlights
Proven truck engine designs: Although the EcoTec3 engines for the 2014 Silverado and
Sierra are all new – sharing just a handful of small parts with previous engines – they build on a
foundation of more than 100 million Small Block engines and billions of real-world customer
miles.
Engines based on the Small Block architecture are typically smaller and lighter than competitive
engines with overhead camshafts, and typically have lower friction. Although package size is
usually not a concern with full-size pickups, lighter weight and lower friction can both contribute
to improved efficiency.
Weight-saving aluminum engine blocks: For 2014, all three engines for the Silverado and
Sierra use lightweight aluminum blocks with cast-in iron cylinder liners. The blocks were
developed with math-based tools and data acquired in GM’s racing programs, providing a light,
rigid foundation for a smooth and strong engine.
The deep-skirt block design helps maximize strength and minimize vibration. Cross-bolted main
bearing caps are secured to the block with four main bolts and two cross bolts each. A structural
aluminum oil pan further stiffens the bottom of the block. The result is an engine that is quieter,
smoother and more dependable, even under the toughest conditions.
Advanced oiling system: The oiling system incorporates a new variable-displacement oil
pump that enables more efficient oil delivery, based the engine’s operating conditions. Its dualpressure control enables operation at a very efficient oil pressure at lower rpm, and then
delivers higher pressure at higher engine speeds to provide a more robust lubrication.
Oil capacity has been increased to six quarts for the 4.3L V-6 and eight quarts for the V-8
engines. All engines use GM’s Dexos oil for increased fuel efficiency and longer oil life, and V8s are engineered to use 0W/20 oil to improve lubrication and reduce friction.
All trucks also feature GM’s oil life monitor, which better protects engines by recommending oil
changes based on actual engine operating conditions and can save owners’ money by avoiding
unnecessary oil changes.
Oil-jet piston cooling: At higher engine speeds, small jets spray oil on the underside of each
piston. This helps reduce piston temperature, enabling the engine to maintain maximum
horsepower and torque, and also reduces engine noise.
PCV-integrated rocker covers: New domed rocker covers house a patent-pending integrated
positive crankcase ventilation system that enhances oil life, reduces oil consumption and
reduces exhaust emissions. The domed sections of the covers contain baffles that separate oil
and air from the crankcase gases, with about three times the oil/air separation capability of
previous engines.
Exhaust manifolds: The exhaust manifolds were developed to improve durability and sealing
and reduce operating noise. The cast iron manifolds feature saw cuts along their cylinder head
mounting flange, which split the flange into three separate sections on the V-6 and four separate
sections on the V-8s, allowing each section to move under extreme hot-cold temperature
fluctuations to virtually eliminate movement of the exhaust manifold gaskets. That helps ensure
proper sealing for the life of the engine and reduces the chance of gasket failure. The exhaust
manifolds also feature triple-layer stainless steel heat shields, which limit heat transfer to the
engine bay and help further reduce noise.
Cooling system, humidity sensor and more: Additional features and technologies of new
Silverado and Sierra engines include:
 A revised cooling system with an offset water pump and thermostat for more efficient
performance
 An air induction humidity sensor ensures optimal combustion efficiency, regardless of
the surrounding air’s humidity
 All engines feature an engine-driven mechanical vacuum pump to enhance braking
performance
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58X ignition system with individual ignition coil modules and iridium-tip spark plugs
All-new “E92” engine controller.
General Motors’ investment in the new EcoTec3 engine family will create or retain more than
1,600 jobs in five North American plants, including Tonawanda, New York, which recently
received upgrades to support its production.
Founded in 1911 in Detroit, Chevrolet is now one of the world's largest car brands, doing business in
more than 140 countries and selling more than 4 million cars and trucks a year. Chevrolet provides
customers with fuel-efficient vehicles that feature spirited performance, expressive design, and high
quality. More information on Chevrolet models can be found at www.chevrolet.com.
GMC has manufactured trucks since 1902, and is one of the industry's healthiest brands. Innovation and
engineering excellence is built into all GMC vehicles and the brand is evolving to offer more fuel-efficient
trucks and crossovers, including the Terrain small SUV and Acadia crossover. GMC is the only
manufacturer to offer three full-size hybrid trucks with the Yukon, Yukon Denali SUVs and the
Sierra pickup. The Sierra Heavy Duty pickups are the most capable and powerful trucks in the
market. Details on all GMC models are available at http://www.gmc.com/, on Twitter at @thisisgmc or at
http://www.facebook.com/gmc.
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