How do the Toyota RAV4 all-wheel drive systems work?

Toyota RAV4 driving off-road

From its introduction in 1994, the Toyota RAV4 was never designed to compete with the off-road capabilities of its Hilux and Land Cruiser siblings. The model name is a contraction of Recreational Active Vehicle with four-wheel drive – a description that identifies the RAV4 as a lifestyle vehicle with the additional benefit of some all-wheel drive performance.

To dismiss the fourth-generation Toyota RAV4 as an urban-only SUV undersells the sophistication of its chassis. Its ability off the beaten track comes courtesy of two different optional all-wheel drive systems designed to keep you safe, under control and mobile in conditions that would likely be impossible in a traditional car.

Let’s take a closer look at these two systems. We begin with the most popular E-Four electronic system found in all-wheel drive RAV4 Hybrid models, followed by the mechanical system found in traditional all-wheel drive petrol and diesel models.

Toyota RAV4 Hybrid E-Four all-wheel drive

In addition to the familiar Toyota Hybrid engine and motor powering the front wheels, models with E-Four all-wheel drive employ a second, rear-mounted electric motor to power the rear wheels. This allows torque to be distributed between all four wheels, improving grip and stability.

In normal driving, all of the car’s power is sent through the front wheels as this is the most fuel-efficient use of the energy. The RAV4’s electronic control unit constantly monitors data such as vehicle speed, accelerator angle and wheel speed to calculate the optimal spread of torque. If it detects a need for more torque at the rear (such as if the front wheels are slipping), it instructs the rear motor to send a precise level of torque to the rear wheels to make up the shortfall.

Up to 60% of the car’s total power can be sent to the rear axle. So when you’re pulling away, going up a hill or driving on a low-traction surface, having a measure of torque delivered to the rear wheels makes it easier to set off in a controlled manner. The E-Four system can also shuffle torque delivery across both axles to deliver a sportier, more assured driving experience.

Toyota RAV4 Hybrid tows a trailer off-road

Towing capacity more than doubles if you opt for a RAV4 Hybrid with E-Four all-wheel drive. Front-wheel drive models can tow up to 800kg but models with E-Four all-wheel drive can tow 1,650kg.

Toyota RAV4 mechanical all-wheel drive

The fourth-generation RAV4 features a programme that co-ordinates every function of the four-wheel drive system, stability control system and electric power steering. Compared with the all-wheel drive setup in the third-generation RAV4, this new management system does not always need to rely on slip detection before deciding on the distribution of torque to each wheel.

Toyota RAV4 Hybrid drives along gravel lane

The driver has the option to come out of this default setting and increase the level of the system’s interaction by engaging Sport mode, activated by a button in the centre console. Like a heightened level of awareness, this mode sends data to the relevant ECU from sensors monitoring vehicle speed, steering angle, throttle input and yaw rate, which the programme then uses to determine the proportion of torque to send to the rear wheels.

Toyota RAV4 4-wheel-drive 1

This is physically actioned by varying the strength of electric current heading into an electro-magnetic solenoid in the control coupling located ahead of the rear differential (see image above). Depending on driving conditions, the amount of torque being directed into the differential can vary by as much as 50%, from the car being entirely front-wheel drive for optimum fuel efficiency to an equal sharing of torque between the two axles.

Four-wheel drive system Toyota RAV4

So accurate is the monitoring of vehicle behaviour that the shuffle of torque between the axles will have already started before any slip or understeer is detected. From the moment the steering is turned, the system automatically adjusts to a 90:10 front/rear torque distribution, priming the car to deliver optimal cornering poise and grip. This simultaneously reduces the load on the front wheels and the likelihood of experiencing understeer.

Should the cornering force go on to exceed the car’s adhesion to the road surface, however, yaw rate controls react within milliseconds to instruct the system to apply up to 50% of the available torque to the rear wheels to improve grip.

Four-wheel drive system Toyota RAV4
RAV4-AWD-05

There are times, such as in snow or on steep gravel tracks, when the driver will know before even setting off that grip levels will be poor. In this instance, it is possible to maximise grip by locking the torque distribution in a 50:50 ratio at speeds up to 25mph. This locked function is activated simply by pressing a button to the left of the steering column, which then illuminates a discreet warning light above the fuel gauge.

Toyota RAV4 all-wheel drive systems: conclusion

Thanks to a minimum ground clearance of 187mm and relatively short overhangs, the fourth-generation RAV4 is capable of riding over heavily rutted tracks and clambering over relatively large obstacles. So although the RAV4 may be categorised as a modern soft-roader, its adoption of Toyota’s technology and four-wheel drive expertise means the RAV4 is anything but ‘soft’.

2014 Toyota RAV4 all-wheel drive badge

83 comments

  1. We have a 63 plate Rav ICON 2.2 diesel automatic. In winter conditions how do we know whether the vehicle is in 4 wheel drive mode. Is there an Indicator light on the dashboard that confirms this.

    1. Hello Tony
      Thanks for your post and hope you are enjoying your Toyota RAV4.
      To answer your question there will be no indication on the vehicle dashboard when the car switches to all wheel drive (AWD) (unless you press the drive lock switch on the dashboard). To explain further your RAV4 has AWD but when for example you are driving normally then AWD may not be required, so to conserve fuel and reduce emissions only the front wheels will be driving the car. The system is designed to operate automatically when it detects that more traction is required then power will be passed to the rear wheels to help improve grip and safety. We hope this helps answer your question but please let us know if you have any other queries.

      1. Thanks for clarifying. For future developments an indicator light showing the 4WD is in action would seem a good idea.

      2. Thanks you for the reply Tony and glad to help.
        We will pass your comments back to the product team for their information.

      3. David,

        I have seen a lot of discussion of 4 wheel drive being equal torque sent to back and front. I am considering a 2015 RAV4. Currently I own a Subaru Impreza, which is the best car I have ever driven in snow. I don’t know how to ask the appropriate question but I do have a simple test.

        If I park a 2015 AWD RAV4 on a hill (pointing up hill) with the two passenger wheels parked on ice, and the two drivers side wheels parked on dry pavement, will I be able to pull away straight up the hill?

        I watched a Honda CRV get stuck with two wheels on dry pavement. My Subaru pulls right out without hesitation. So I know all AWD is not created equal, but I don’t know what question to ask. Can you help?

      4. Hi Steve
        Thanks for your post.
        A very interesting question and we do understand the analogy. To be 100 per cent accurate it would be good to know which RAV4 (engine and gearbox) appeals the most. We could then be a bit more specific. Overall though the RAV4 AWD system does have limited slip diff capabilities to the front wheels meaning it would feed slightly more torque to the wheel on the dry surface. The amount of torque is limited but hope this helps explain a bit more. If you need any more advice let us know or if we can help in arranging a test drive.

      5. David,

        I was referring to to the 2015 LE model with the AWD option. Interesting, I seem to be getting more support from the UK than the US. It sounds as though if I buried the passenger wheels in snow and had the drivers wheels on dry pavement the RAV4 AWD would get stuck if the torque is limited. Thank you for your help!

      6. Hi Steve
        Thanks for the post and sorry for the delay in replying.
        No problem with the advice but just want to point our reply was based on UK RAV4 specifications. As we would not know the spec of US RAV4’s we do recommend that you double check this as a precaution. Hope this helps.

  2. When the 4 wheel drive is locked in there are occasions when still additional help is required in, say, snow. A differential lock should be included also.

  3. Hi Todd
    Thanks for your post and for your interest in the Toyota RAV4.
    The rear bias only tends to kick in as and when it is required. To help explain further, if you are travelling at 60 mph along a long straight motorway then there is no need for this as the car will use front wheel drive only to optimise fuel consumption. If you are travelling up a mountain road then rear bias may be used if the car detects slippage or extra traction is required.
    Hope this helps explain but let us know if you have any other questions.

  4. so..if I understand correctly. The default mode is front wheel drive unless slippage is witnessed or I am traveling under 25 mph?

    1. Hi Bill, you’re virtually there. The RAV4 four-wheel drive will automatically kick in during more advanced situations as well, for example; when cornering, for extra stability the steering will adjust as required for maximum traction and stability. We hope this helps.

    1. Hi Laura,
      Thank you for your post. This is dependent on which year RAV4 you have. Please can you let us know the year of your RAV4 and we will be able to help you further. Many thanks.

  5. Hi Iv got a rav 4 automatic 1993 will thus have a button on the dash bird to put in to a 4( wheel drive in bad snow

  6. Hi
    I have UK rav4 when am driving on a straight way no rain even snow and the road conditions is dry when reach 100km/h the slippage light illuminated on dashboard can you please where I can start

  7. Hi Andrew,
    Thank you for your post. There are many factors which may influence this, therefore it is hard for us to tell what the issue is. We believe this may have something to do with VSC (Vehicle Stability Control). Have you spoken with your local Toyota dealer who will be able to provide a hands on investigation? Many thanks.

  8. Hi, I am driving RAV 4 2016 Module 4 WD, from KSA – need to know how the lock centrally off when I switch off the CAR and remove the Key as the car lock still on and other person can not exit CAR
    thanks Mohd M

    1. Hi Mohamed,
      Thanks for your comment. We would advise contacting your nearest Toyota dealer who will be able to help you with this. Many thanks.

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