2013 The new Toyota RAV4: Driving performance
- Increased body rigidity for greater handling stability and improved steering response
- Retuned front and rear suspension and revised Electric Power Steering for enhanced steering feel and precision
- Integrated Dynamic Drive System — upgraded all-wheel drive system with Sport mode for enhanced on-road agility
- Available Down-hill Assist and Hill Start Assist Control for greater vehicle control
Successive generations of RAV4 have established a reputation for their ride comfort, ease of driving, manoeuvrability and reassuring capabilities on challenging road surfaces.
In conjunction with a new, more comfortable and focused driving position, the new RAV4 builds on these key attributes, retuned front and rear suspension systems, revised Electric Power Steering, and a newly developed Sport mode for its advanced, all-wheel drive, Integrated Dynamic Drive System.
In combination, these developments give the new RAV4 greater stability and agility on both wet and dry roads, offering customers a confidence-inspiring, more intuitive and engaging driving experience.
The new RAV4 is also available with both Down-hill Assist and Hill Start Assist Control. Fitted as standard to all vehicles equipped with automatic transmission, Down-hill Assist Control automatically regulates gear selection, engine speed and the individual wheel braking capabilities of the ABS system to help the driver maintain a constant speed during both on- and off-road descents.
The adoption of high and ultra-high tensile steel in the construction of the bodyshell allows for the use of thinner sheet with no loss of strength, thus reducing weight to enhance fuel efficiency.
It has been used more widely throughout the new RAV4, including in such strategic locations as the reinforcement of the front cowl attached to the A pillars, the rear axle braces and the rear suspension coil spring upper supports.
Body rigidity has been improved through an increase in the number of spot welding points around both front and back door openings, enhancing yaw and steering response.
Retuned Front and Rear Suspension Systems
The new RAV4 shares the MacPherson strut front and lightweight trailing arm double wishbone rear suspension of its predecessor. However, both systems have been revised to optimise ride comfort whilst enhancing steering feel.
The spring rate of the front suspension has been revised. The increased rigidity of the front suspension member stabilizer bracket promotes a smoother steering feel when cornering. Contributing to both enhanced steering feel and improved ride comfort, friction in the inner structure of the shock absorber has been reduced, the characteristics of the stabiliser bushes have been optimised, and friction within them reduced through the use of a fluorine coating.
Similar measures have been adopted for the rear suspension system. The spring rate has been revised, and the diameter of the stabiliser bars increased to optimise the front/rear distribution of roll rigidity. The rear shock absorber and stabiliser bushes benefit from the same revisions as those made to the front suspension.
Revised Electric Power Steering
Both the installation and the ECU control of the Electric Power Steering (EPS) have been revised to combine a more comfortable driving position with improved steering precision and feel.
The steering column has been tilted downward by 1 degree, and the installation angle of the new steering wheel has been changed from 27.6 to 25.3 degrees, moving it closer to the driver.
The Electronic Control Unit (ECU) and EPS have been integrated to reduce vehicle weight, and the adoption of a resin-coat intermediate shaft and revised software compliance has improved steering precision and feel.
Integrated Dynamic Drive System
The new RAV4 is available with either front-wheel drive or the Integrated Dynamic Drive System, an upgraded version of Toyota's advanced all-wheel drive technology featuring a new Sport mode.
The Integrated Dynamic Drive System is a sophisticated, high-speed interactive management system which coordinates control of the RAV4's Dynamic Torque Control AWD, Vehicle Stability Control (VSC) and Electric Power Steering (EPS) systems to enhance the compact SUV's performance, handling and safety.
Using information from various sensors (speed, steering angle and yaw rate), the Dynamic Torque Control AWD system continuously controls the torque transfer between the front and rear wheels via an electromagnetically controlled coupling positioned in front of the rear differential.
Front to rear torque distribution can vary from 100:0 to 50:50, with front-wheel drive (100:0) automatically engaged under normal driving conditions to improve fuel consumption.
In normal mode -when neither Sport mode nor Lock mode are activated- torque transfer to the rear wheels now takes place not only when the front wheels are beginning to spin on slippery surfaces (as in the third generation RAV4) but also when the system detects understeer during cornering on road. As a result, the overall agility and driving performance of the vehicle is enhanced during both on- and off-road driving.
When the new Sport mode is selected, torque transfer to the rear wheels begins even before understeer develops. From the moment the steering wheel is turned, the Dynamic Torque Control AWD System operates a newly developed pre-torque control, automatically introducing a 90:10 front/rear torque distribution to help cornering force by transferring traction torque to rear.
If actual understeer develops, torque transfer to the rear wheels is automatically increased by up to 50% through a new yaw rate feedback control, to provide front tyres with improved lateral grip.
As well as activating the 'Dynamic' behaviour of the system's front to rear torque transfer, the new Sport mode also decreases the RAV4's power steering assistance by 20% and, depending on version, sharpens throttle response and offers higher revs for a more dynamic, sporting driving experience.
For off-road driving, the system incorporates an AWD Lock button. This allows drivers to lock torque distribution in a fixed, 50:50 ratio at speeds up to 40 km/h. Above this speed, the system automatically reverts to Normal mode.
From Integrated Active Drive System to Integrated Dynamic Drive System
The third generation RAV4 used Integrated Active Drive System, in which torque control was managed by an Active Torque Control 4WD system. The new RAV4 now uses a Dynamic Torque Control AWD System.
Compared to the third generation car, the new RAV4 keeps the following functions:
- Starting Control: traction performance when starting on snowy or muddy roads is ensured by increasing the rear torque distribution up to 50%. At speed above 25 km/h, the driving control switches to normal driving control.- Normal driving control: on highways or urban roads, the rear torque distribution is reduced to 0% to enhance fuel efficiency. When detecting slippery roads in which wheel skidding occurs, torque control is immediately activated to ensure driving stability.- VSC co-operative control: When the front wheels skid and the vehicle runs outside the driver's intended path, EPS assists for the turning direction (by creating a torque in the steering wheel in order to show to the driver the right manoeuvre to do ), and torque is distributed to the rear wheels.- Braking control: AWD is cancelled to enhance the effects of ABS a and the VSC System.- Lock mode control: when the driver pushes the LOCK mode switch. 50% of torque is transmitted to each axle to enhance escape performance in situations such as when the vehicle is stuck.
The new function added on top of these 5 control modes is:
- Cornering control: Yaw rate feedback control is used to adapt rear wheel torque to assist cornering performance by generating optimal drive force distribution and balancing the load between front/rear wheels. With Sport mode, from the first steering input, 10% of the torque is directed to the rear wheels at the start of the corner which can increase to a maximum of 50% during cornering to ensure driving stability and a fun to drive experience.
Thanks to cornering control, Sport mode helps the driver to maintain his intended trajectory and, at the end, have more enjoyable driving experience.