That Toyota planned to offer a hybrid-electric powertrain in its 2013 Avalon was hardly a surprise within the industry, but the car’s 40-mpg combined EPA fuel economy target announced June 25 got widespread attention. The all-new D-segment sedan is the first in its class to bring a full hybrid powertrain—in this case Toyota’s proven input-powersplit Hybrid Synergy Drive system—to the premium midsize segment.
The hybrid powertrain is shared with the Camry and Lexus ES hybrids. It features the company’s 2AR-FXE 2.5-L Atkinson cycle I4, a pair of electric motor/generators within the transaxle, a 244.8-v nickel-metal hydride air-cooled battery pack rated at 34 kW (45.6 hp), and a liquid-cooled power control.
Total system output is rated at 200 hp (149 kW). It offers three operating modes: pure EV (limited to less than 25 mph for up to one mile), Eco, and Sport. The Avalon Hybrid is currently being tested by the EPA for certification, with the program’s Chief Engineer Randy Stephens “confident that we’ll achieve 39 mpg city and 40 mpg highway for the combined 40-mpg rating.”
He credits Avalon’s 0.28 Cd aerodynamics, and reduced curb weight (by 150 lb/68 kg) compared with the outgoing model, as other keys to the car’s impressive overall efficiency.
The Eco drive mode engages the combustion engine but limits throttle response and HVAC output, to help improve overall efficiency. The Sport mode gives a sharper throttle tip-in feel which goes along with the thoroughly re-engineered Avalon and its sportier, more fun-to-drive nature. (AEI is preparing a full development story on the car.)
Stephens, who led Avalon’s U.S.-based engineering and development, told AEI the hybrid powertrain was in the program from first concepts. He noted that the hybrid version’s fuel economy (pending EPA testing) will exceed that of any vehicle in its competitive set (Buick LaCrosse, Hyundai Avenza and Genesis, Chrysler 300, Nissan Maxima, and Ford Taurus). For example, the 2012 LaCrosse with 2.4-L engine equipped with eAssist (a P1-type hybrid system) is rated at 29 mpg combined (25/36 mpg city/highway).
And by comparison Ford’s current-generation Fusion Hybrid, which is not among Avalon’s direct competitors as defined by Stephens’ team but is formally an EPA midsize vehicle, is rated at 39 mpg combined city/highway (41/36 mpg).
The Avalon’s conventional powertrain is comprised of Toyota’s 2GR-FE, 3.5-L gasoline V6 paired with a 6-speed planetary automatic. The engine is rated at 268 hp (200 kW) and 248 lb-ft (336 N•m). The car’s new Aisin transaxle features a numerically lower (3.23:1) differential gear drive ratio, which is expected to enable this powertrain to achieve an EPA-rated 25 mpg combined (21 city/31 highway), pending final certification.
The new 2013 Avalon is based on Toyota’s ubiquitous K architecture, which also underpins Camry, Lexus ES and RX, Toyota Venza and Highlander, and other vehicles. In a departure for Toyota, American design and engineering teams at Calty in California, and the company’s technical centers in Michigan, handled development. It will be built in Georgetown, KY.