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

87 comments

  1. Hi Toyota, I have a 2019 RAV4 2.2Petrol with AWD. How is the rear axle powered? Is it just the 2 electric motors or is there a conventional prop shaft driving a differential on the rear axle as well? I want to know because my car was hit (while stationary) by a rise and fall bollard coming up underneath the car while I had to wait for pedestrians to get out of the way. What I really want to know is whether it could have hit a prop shaft.

  2. Hi, does the 2020 RAV4 AWD hybrid have an open rear differential or a limited slip rear differential. I use my current vehicle off-road quite a lot and having a limited slip rear diffential is very useful when the ground is very slippery. Would like to know this to help me decide if a RAV4 will be suitable for my needs

  3. Hi Martin,
    Thanks for getting in touch.
    RAV4 Hybrid AWD features an electric motor on the rear axle. It distributes power to left and right wheels using an electromagnetic control coupling, as power to the rear axle comes from a dedicated electric motor.
    The car is extremely capable off-road, and features a Trail Mode that can send torque to all four corners of the car.
    What do you use the car for?
    Thanks.

  4. Hi Toyota team. I have a 2007 Full time 4 wheel drive. It has no button for diff lock or traction control. How does the 4 wheel work?

    1. Hi Arthur,
      Thanks for getting in touch with us.
      For specifics relating to your vehicle’s systems, we would recommend contacting the Toyota distributor in your region for further help with your query.
      Thanks.

  5. Hello Toyota
    1) Is the 2021 Rav4 petrol engine connected to the front wheels mechanically?
    2) I have been told by a dealer that there is a generator at each wheel that charges the transmission battery and provides additional braking force when the brake pedal is depressed. Is that correct?
    Graeme Boon
    New Zealand.

    1. Hi Graeme,
      Thanks for getting in touch.
      Yes, the petrol engine is connected to the front wheels. In 4WD models, the rear wheels are powered by an additional electric motor. Toyota’s hybrid system charges the battery in two ways. Firstly, the petrol engine drives the generator to charge the battery. The second method is through regenerative braking. Every time you put your foot on the brake or lift off the accelerator, the system diverts energy back to the battery where it is, in effect, recycled. Instead of the energy being lost as heat or noise from the brakes, it is captured and then used to power the electric motor later. This is particularly efficient in stop-start traffic where the system recovers and stores a great deal of energy, making the car more efficient overall.
      Please contact Toyota in your region if you have further questions.
      Thanks.

  6. Hi. Regarding a 2018 RAV4 AWD I’m looking to buy – in addition to the rear diff coupling, do they have rear drive shafts going to each wheel too, for total 4 drive shafts/CV joints? Thanks ;>) [btw, I have a 2017 RAV4 LE FWD and mpgs are incredible, avg 32, high 37. Looking at the 18 with 5800 mi lease turn in, vs mine with 58k miles.]

    1. Hi Paul,
      Thanks for your comment. We’re so glad to hear that you’re loving your RAV4.
      We can only advise on UK specification vehicles, so we would recommend contacting Toyota in your region for further help with your query.
      Thanks.

  7. Hi, I just purchased 2021 RAV4 XLE Premium last October 2020. On February 15, the car won’t change gear from park. Message showed Hybrid battery decrease. It was a winter storm here in Chicago that day and very cold temperature. I googled how to trouble shoot, opening the gas tank, and the car started. The engine light is on and message to take the car to nearest dealer. I was very upset and prostrated that I had to call off work and this is a brand new car, so I did not expect that I will have a problem so soon. Mechanic did not find anything wrong, so he just charged up the battery. What if this happens again I asked? They no answer for me….

    1. Hi Milagros,
      Thanks for getting in touch.
      We can only advise on UK specification vehicles, so we would recommend contacting Toyota USA for further help with your query.
      Thanks.

  8. Hi.During a long climb uphill on a lexus nx300h 4wd, then it smells like a burnt palasik.Can you tell please me what it could be? 2020 car, mileage 3500. Thank you

    1. Hi Dmitrij,
      Thanks for your comment.
      We are unable to diagnose your vehicle over the internet, so we would recommend taking your vehicle to a Toyota Centre in your region so that any potential faults can be assessed.
      Thanks.

    1. Hi Lee,

      You can use the buttons on the steering wheel to change the display in the instrument cluster. Use the left or right arrows to navigate to the Vehicle Information Display section. It has an icon with a car and an ‘i’. Then use the down/up arrows until you get to the AWD system display screen. You should see the car’s four wheels, with cars next to them, indicating how much torque is being sent to each wheel.

      Thanks

  9. Does the engine kick in when your over 20mph speed or is there any specific number for Rav4 2021 model?I am looking buy one

    1. Hi Syed,
      Thanks for getting in touch. It’s great to hear that you’re considering a RAV4! We assume you are referring to the electric motor vs the petrol engine in the RAV4 hybrid?
      There’s no specific speed at which the petrol engine kicks in. The type of fuel source being used is dependent on a number of factors, including driving style and driving conditions.
      In our hybrids, the electric motor and petrol engine work in tandem, with the fuel source constantly switching depending on which is best for the current conditions to provide the greatest efficiency and performance.
      We would recommend test driving the RAV4 to check it will suit your requirements.
      Thanks.

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