- 2018/1/16 12:00
- TNGA-based 2019 Toyota Avalon features new hybrid system
16 January 2018
Toyota unveiled the new fifth-generation Avalon at the North American International Auto Show in Detroit. Avalon received an all-encompassing makeover by Toyota’s US-based design, engineering, and manufacturing entities at Calty Design Research Inc. (Calty) in Ann Arbor, Michigan; Toyota Motor North America Research and Development (TMNA R&D) in Saline, Michigan; and Toyota Motor Manufacturing, Kentucky, Inc. (TMMK) in Georgetown, Kentucky, respectively.
Underpinned by the Toyota New Global Architecture (TNGA) K Sedan platform, the 2019 Avalon is powered by two new TNGA powertrains: a punchy 3.5-liter V6 (2GR-FKS), and, a 2.5-liter Dynamic Force four-cylinder Toyota Hybrid System II (THS II) with 650-volt electric motor (A25A-FXS) and Continuously-Variable Transmission (CVT). Avalon Hybrid continues to be the only full hybrid vehicle in the segment. Avalon comes in four available grades: the athletic XSE (all-new) and Touring, as well as the more opulent XLE and Limited. Hybrid grades include XLE, Limited, and XSE.
2019 Avalon Hybrid
The TNGA-derived V6 develops more power with less fuel consumption than before. Achieving the two took the application of D-4S direct injection, along with an updated VVT-iW (Variable Valve Timing-intelligent Wide) variable valve timing system.
The VVT-iW system is employed on the intake cycle, with VVT-i (Variable Valve Timing - Intelligent) activated on exhaust. With VVT-iW in place, engineers ensured optimal torque creation at all engine speeds, and minimized pumping losses during the closing of intake valves, which furthered fuel efficiency. The use of Atkinson cycle, too, reduces the V6’s fuel appetite, particularly in cold climates or during wide-open throttle (WOT) situations.
Other V6 specifications include a 11.8:1 compression ratio and 3.7 in. bore and 3.3 in. stroke.
An all-new TNGA 8-speed Direct Shift-8AT automatic transaxle gearbox (UA80E) channels power to the Avalon’s front wheels. Its revised logic control better matches vehicle speed, engine speed, and torque engagement, while also facilitating poised downshifts.
Its eight gear ratios balance wide range and close ratios, therefore enhancing power application and fuel efficiency. A wider range, specifically at the increased 8th gear ratio, allows for improved high-speed cruising fuel economy. Close ratios at the mid-range gears improve passing power.
A new torque converter provides a wider range of lock-up operation (versus the outgoing 6-speed automatic transmission) to imbue a more enveloping and direct driving feel. The converter contributes to low fuel consumption and passenger comfort, since engine revving is kept to a minimum.
Avalon Hybrid. A new TNGA 2.5-liter four-cylinder Dynamic Force Engine is more fuel efficient, runs cleaner, and is more powerful than previous iterations, and features enhanced thermal management. Technologies required include: Dual VVT-i with VVT-iE (Variable Valve Timing intelligent system by Electric motor); D-4S (Direct injection 4-stroke gasoline engine Superior version) direct injection and laser-clad valve seats; longer stroke (4.07 inches; bore remains at 3.44 inches) and high compression ratio (14:1); multi-hole direct fuel injectors; a variable cooling system; cooled Exhaust Gas Recirculation (EGR) system; and a full variable oil pump.
Instead of oil pressure, its Dual VVT-i with VVT-iE variable valve system employs an electric motor to control variable valve timing, which aids fuel efficiency and promotes cleaner exhaust emissions (this is especially helpful in cold climates). The D-4S direct injection combines higher-pressure direct fuel injection (DI) and lower-pressure port fuel injection (PFI), and applies each method of injection based on specific driving parameters. Furthering fuel efficiency are new multi-hole nozzle direct injectors (six holes per injector).
The four-cylinder Dynamic Force Engine is married to an all-new Toyota Hybrid System II powertrain that’s been engineered to inspire both spirited driving and fuel consciousness. THS II uses two electric motors—MG1 and MG2—to supplement the charging of the hybrid system’s Nickel-Metal Hydride (Ni-MH) battery pack, while MG2 assists the engine.
New for 2019, the highly compact battery pack now resides under the rear passenger seat (instead of the trunk), as a result of improved TNGA packaging and for the betterment of a lower center of gravity. THS II’s new lighter, smaller Power Control Unit (PCU) packages microcontrollers within a power stack structure that’s located above the transaxle—all with the goal of lowering mass to better handling composure.
Efficiencies on many levels are seen with the implementation of the new PCU. Energy loss in the conversion efficiency of the transaxle and electric motor is reduced by approximately 20%, and its cooling system’s energy loss is cut by approximately 10%. The PCU’s DC-DC converter—which converts a direct current from one voltage level to another—is optimized to reduce overall power consumption. Dimensionally, DC-DC converter’s output filter is smaller, lighter, and quieter for an improved passenger experience.
Auto Glide Control (AGC), yet another of Avalon’s fuel-saving technologies, automatically calculates efficient coasting. When driving normally, engine braking will slow the vehicle down when the driver lifts off from the accelerator pedal. However, to avoid aggressive engine braking, AGC limits the loss of vehicle speed through an automatic drive setting that acts more like a neutral gear, allowing the vehicle to coast to the stoplight.
A light indicating “AGC” is illuminated on the Multi-Information Display (MID) when AGC is active to alert the driver that less deceleration torque than normal is currently being used. AGC can only be activated when the vehicle is being operated in the ECO drive mode setting.
A new Sport drive mode applies power from the hybrid system for improved acceleration and, as a bonus, all drive modes, including Sport, can each be used while EV mode is activated. With Shiftmatic technology, XSE trim drivers can “shift” through the Continuously-Variable Transmission’s six simulated gears via steering-wheel mounted paddles or the gearshift.
Drive personality. Avalon offers an array of available sport-oriented tools—which, together, represent a Toyota first: Adaptive Variable Suspension (AVS), Intake Sound Generator (ISG), grade-specific exhaust baffle tuning, Active Noise Control (ANC), and Engine Sound Enhancement (ESE). A more comprehensive four-level drive mode selection—which includes Eco, Normal, Sport/ Sport+, and Custom—is available on Touring trim, also. All other grades receive a three-level drive mode selection (Eco, Normal, Sport).
Touring’s standard Adaptive Variable Suspension (AVS) provides real-time damping control to maximize controllability and sharp handling. The astute setup reduces Avalon’s posture fluctuations under hard or sudden directional changes, limits body movements, and yet absorbs nasty road undulations for a comfortable, flat ride.
AVS relies on three primary systems to accomplish its mission: shock absorbers at each corner that have solenoid control valves for independent wheel control; advanced front and rear G Sensors to comprehend the vehicle’s condition; and, an intelligent central ECU that reacts to the G Sensor’s observations by dictating exact damping adjustments to the shock absorbers’ solenoids.
Levels of AVS’ damping force are continuously variable, with a maximum of 650 steps. Changes in solenoid force—which restrict absorber fluid and, thus, damping—happen in an incredible 20 milliseconds. Drivers can adjust Avalon’s ride feel with the simple depression of a button—Normal mode prioritizes comfort, while Sport+ emphasizes handling with tauter, highly responsive footing without diminishing Avalon’s celebrated ride suppleness. Progressing from Normal to Sport+ also benefits Avalon’s liveliness. For example, throttle response becomes quicker, the Electronic Power Steering’s (EPS) feel emphasizes feedback, and its engine sound is enhanced through ESE.
The new multi-link rear suspension allows for the enhancement of many positive performance attributes, such as a wider rear track, lower center of gravity, and an aggressive stance. Revised trailing arms have been installed at a higher position to place the pivot axis of the tire rearward for better bump absorption. The setup’s shock absorbers are tilted forward, too, to realize a suppler ride. Bushings on the trailing arms and arm joints further mask passing road imperfections.
Although not equipped with AVS, XLE, Limited, and XSE take full advantage of their innately sporty platform and multi-link rear suspension and, to them, add thicker stabilizer bars and stiffer spring rates for maximum handling dexterity. Spring stiffness, for example, is increased 25% when comparing XLE to Limited; stabilizer bar stiffness is up 38% and 62%, front and rear, respectively, when progressing from XLE to XSE.
Design. Leveraging the adaptable TNGA core, the Calty team penned Avalon’s exterior to be longer, lower, and wider than before. Never-before-accomplished stamping methods also aided in the deep draw panels that express distinguishable sculpted forms. Complex surfaces could now be shaped, such as at Avalon’s door handles that coincide with its profile’s bold character line. A distinct, carved lower rocker panel behind the front wheels visually exemplifies the benefits of TNGA.
Avalon extends its rear cabin farther by another 7 inches, and elongates side quarter glass and downward tapered C-Pillar by 2.2 inches. Engineers and designers implemented a 0.31-inch radius corner—the tightest ever for Toyota—fore of the steep pillar.
Avalon’s various height measurements have been trimmed: overall (by 1 in. to 56.5 in.), cowl (by 1.2 in.), and rear deck (by 0.8 in.). So too have front and rear overhangs (down 0.4 in. and 1.0 in., respectively). It features a wider front (up 0.4 in.) and rear (up 1.5 in.) tracks, width (up 0.8 in. to 72.8 in.), and wheelbase (up 2.0 in.).
Safety Tech. Avalon’s standard Toyota Safety Sense P (TSS-P) suite of safety systems and technologies represents one step closer to achieving Toyota Motor Corporation’s ultimate goal of zero casualties from traffic accidents.
TSS-P bundles cutting edge active safety technologies including Pre-Collision System with Pedestrian Detection (PCS w/PD), Full-Speed Range Dynamic Radar Cruise Control (DRCC), Lane Departure Alert with Steering Assist (LDA w/SA); and Automatic High Beams (AHB). Additional standard safety technology includes Blind Spot Monitor (BSM) with Rear Cross Traffic Alert (RCTA) and Back Guide Monitor (BGM).
Also available are Panoramic View Monitor with Alert (PVMA) and Intelligent Clearance Sonar (ICS), which now includes a Rear Cross Traffic Braking (RCTB) system.
All 2019 Avalons have 10 standard airbags and Toyota’s Star Safety System, which includes Enhanced Vehicle Stability Control, Traction Control, Electronic Brake-force Distribution, Brake Assist, Anti-lock Braking System, and Smart Stop Technology. All Avalons also come equipped with a standard backup camera.