Compared to the previous-generation Avalon, this 2013 powertrain combination offers improved fuel economy, performance, superior shift feel and response, with upgraded drivability and quietness, according to Toyota.

This enhanced powertrain’s programming has been updated to offer ECO, NORMAL, and SPORT Modes.

• The ECO mode prioritizes fuel efficiency by reducing power application at lower speeds and reducing energy consumed by the air-conditioning system.

• The SPORT Mode provides increased acceleration responses though altered engine control unit (ECU) programming, and it offers a more direct and responsive EPS programming to enhance steering feel.

The new transaxle is equipped with a numerically lower differential gear drive ratio (3.23), designed to help improve fuel economy. The V6-powered 2013 Avalon achieves an EPA-rated 25 mpg combined, 21 city, 31 hwy (9.4, 11.2 and 7.6 L/100km, respectively).

The transmission operation has been made more efficient and responsive with the adoption of a flex-start control feature lock-up clutch. With lock-up control, the transmission’s torque converter fully engages at a lower rpm during standing starts to improve acceleration response and help suppress unnecessary engine revolutions. The new transmission is also kept at an optimal temperature with an automatic-transmission fluid warmer, helping enhance efficiency.

The multi-mode automatic transmission console shifter offers a D range and can be moved into an S-mode gate, which allows manually operated sequential shifting using the console shifter or available (Touring and Limited models) steering-wheel-mounted paddle shifters. The gear can be selected by moving the shifter up to (+) position or lower using the (-) position to experience highly responsive shifts. By using the paddles or in S-range, the transmission uses a quick responding shift-logic that includes throttle blipping for downshifts. The gear changes and range-of-gear selections are displayed in the color multi-information display.

Under the hood of the hybrid. Click to enlarge.

Avalon Hybrid. The new Avalon hybrid features a full power-split hybrid system, coupled with reductions in vehicle weight and improvements in aerodynamics.

The Avalon Hybrid features a 2.5-liter, Atkinson-cycle, four-cylinder engine, a 244.8-volt NiMH battery pack, and a pair of electric motor/generators within the transaxle. A power-control unit located in the engine compartment houses an inverter, a DC-DC converter, a step-up converter (raises voltage to a maximum of 650 volts) and the hybrid-drive ECU, which governs the seamless operation of electric-motor power application and regenerative braking. The power control unit relies on liquid cooling to maintain an efficient temperature.

The Avalon Hybrid achieves a total system output of 200 hp (149 kW) and offers three modes of operation: EV, ECO and SPORT. The Avalon Hybrid models achieve an EPA-rated 40 mpg in the city, and a 39 mpg on the highway for a combined 40 mpg EPA-rating.

The 2013 Avalon Hybrid offers an EV mode that, under certain conditions, allows the vehicle to operate solely on electric propulsion. EV mode can be engaged, provided other conditions are correct, for up to one mile (1.6 km) at speeds up to 25 mph (40 km/h), providing an all-electric option that is convenient in residential areas or parking garages.

The ECO drive mode engages the gasoline motor, but reduces throttle response and HVAC output to help improve overall efficiency. The SPORT Mode takes full advantage of the new Avalon’s dynamic character, improved chassis, and enhanced suspension by altering the engine’s throttle response and enhancing steering feel.

The Avalon hybrid’s battery pack comprises 204 cells and is located in the vehicle trunk behind the rear seats, while still providing ample trunk space. The scroll casing for the battery cooling system’s blower fan has been designed to produce extremely quiet and efficient airflow, helping reduce interior noise and elevating refinement. The power-control unit, located in the engine bay, houses the inverter and DC-DC converter.

The efficient hybrid transaxle in the new Avalon contains two high-output electric motor/generators, a power-split device, an open differential and the final drive ratio. Motor/Generator 1 (MG1) is used to start the gasoline engine and generate the energy that is returned to the battery to power the system. Motor/Generator 2 (MG2) is primarily responsible for electric drivetrain propulsion and regenerative braking. The hybrid vehicle transaxle also incorporates a flywheel-damper design that helps reduce noise and vibration during engine engagement.

The Avalon’s engineering development was led by a group based at Toyota Technical Center in Ann Arbor, Mich. Continuing a North American focus, the 2013 Avalon will be assembled at theToyota Motor Manufacturing Kentucky (TMMK) facility in Georgetown, Ky.