The fourth-generation BMW X3 begins its final development tests and trials with a still camouflaged body before finally being unveiled in June.

We were able to drive and test the new BMW X3 2025 exclusively in Miramas, in the south of France, where the BMW Group has had an impressive private facility for more than 30 years where future BMW models are put through their paces before going to market.

These facilities, which are completely isolated from the outside world, include a high-speed oval, a motorway simulator, sound tracks, several circuits with different surfaces and gradients, a handling circuit, an off-road area and an infinite number of pits and workshops where each of the prototypes can be worked on in comfort.

BMW X3 2025: The fourth generation looks like this

There are no official details yet on the new generation of the X3, which is essential BMW's best-selling model in the world and has sold 3.5 million units over its 20-year history.

Gallery: 2025 BMW X3 preview

Because of the camouflage, we weren't able to see its final design, hidden under a layer of black vinyl with white stripes and sheets of fibre strategically placed in different parts of the bodywork, so as not to give any clues as to its silhouette.

Despite the camouflage, its design seems to be a continuation of the previous model, and at the front we can recognise a grille which, although it has increased in size, will not be as large and controversial as on other models from the brand. Behind the vinyl and fibre, we can also make out a front end similar to that of the BMW 2 Series Coupé.

Although the final figure has not been confirmed, the length of the body has been increased by a few centimetres, improving rear-seat space and overall boot capacity. As for the rear design, although the rear lights are difficult to recognise, there are no major changes that could herald a total breakthrough in this area.

BMW X3 2024 test (prototype)

BMW X3 2025 camouflage, rear view

We analyse the engines

What we do know is that there will be four- and six-cylinder petrol and diesel engines, and they'll all feature a 48V micro-hybridisation system.

For now, the most powerful petrol variant will be the M50i xDrive M Performance with around 400 PS (as in the current generation, there will be an M version with over 500 PS). There will also be plug-in hybrid versions with electric ranges in excess of 60 miles and a 100% electric version called the iX3, which is more powerful and more efficient, with a reduction in energy consumption compared with the current generation.

BMW X3 2025 (prototype)

Inside, everything was covered in fabric, so we didn't get to see the final design. What we did see was that underneath the fabric was an interior similar to that of the BMW X5 and other current models from the brand, with the main new feature being the curved one-piece screen that serves as the main instrumentation and multimedia system.

We also notice that the physical buttons for the air conditioning have disappeared and are now controlled from the multimedia system screen (I'm not entirely convinced). Another important change is to be found between the two seats, where the simple and practical gear selector has disappeared, replaced by a more minimalist, but less precise and intuitive button.

Another new feature concerns the air outlets, the flow of which can be adjusted via a touch-sensitive surface on the dashboard and door panels, so that the amount of air leaving the side air vents can also be controlled.

BMW X3 2025 test (prototype)

BMW X3 2025: developed under the worst possible conditions

The test programme to which BMW prototypes are subjected involves several stages before the final model is marketed. These include travelling thousands of miles in different parts of the world, subjecting the prototypes to the most extreme conditions for each of their mechanical, electronic and hardware components.

The prototypes cover thousands of miles on the scorching roads of the Kalahari desert in southern Africa, where they carry out tests in hot climates.

They test the air-conditioning and cooling systems, the possible fatigue of materials under the effect of solar radiation and heat, or the way in which the temperature affects the various electronic elements such as the control units and batteries in the electrified models. Components such as suspension, steering, engine and brakes are also pushed to their limits on rough roads and on all kinds of gravel and sand tracks.

The tests to which BMW prototypes are subjected also include extreme cold tests in the Arctic Circle, where all the above-mentioned components are tested at temperatures that, in many cases, do not exceed -20°C.

BMW X3 2024 (prototype)

Prototype BMW X3 2025 - off-road driving

BMW X3 2025: final tests before launch

During our test day at the Miramas circuit, we were able to accompany the engineers who were carrying out the final tests of the X3 2025 on virtually final models, with the exception of a few adjustments to the chassis and interior, where many plastics did not match the materials and tolerance levels that the production models will have.

These tests involve setting the entire powertrain, which can be adjusted electronically, such as the suspension and steering, to the different driving modes available in the BMW X3 2025.

BMW X3 2025 (prototype)

The ADAS (Advanced Driver Assistance Systems) are also calibrated, both in simulated and real-life situations, to make them much more accurate and avoid false performance throughout the car's life.

The day was divided into four parts: automatic driving and ADAS tests, driving on the handling track to test the various dynamic settings of the chassis, driving on the open road and an interview with the engineers where we were able to discover the M50i xDrive M Performance variant.

BMW X3 2025 (prototype)

BMW X3 2025: getting to grips with the car

We started the morning in a BMW X3 2025 Plug-in Hybrid to see how the enhanced driver assistance systems work, thanks to the new cameras, radar (with a range of up to 300 metres) and sensors that the BMW X3 2025 is equipped with throughout the car.

We accelerate so that the car automatically applies emergency braking when it detects a stationary car in our lane. OK, the previous generation BMW X3 already did this, but it's now much more precise, able to 'see' what's in front of it sooner.

Even if you're not in the same lane, the BMW X3 2025 detects that you're in danger of hitting it and applies a braking force that can even be released if the driver manages, at the last moment, to prevent the car coming to a complete stop, thereby reducing the risk of another vehicle hitting you from behind.

BMW X3 2024 (prototype)

Prototype BMW X3 2025, emergency braking system

The next test consists of carrying out the same exercise, but with a pedestrian, a cyclist and a child (it also detects scooters). In the last two cases, these are new functions, as they were not previously available.

Another new feature is motorbike detection at a crossroads. To do this, we launch the car at 60 km/h (37 mph) and the X3 2025 is able to come to a complete stop at a crossroads and detect a motorbike right in the blind spot. On another pass, we slow down and repeat the exercise. In this case, the BMW X3 2025 calculates that it is not going to hit the motorbike and, although it passes just inside the blind spot, it brakes slightly. It is truly amazing to see how the car is able to analyse everything that is happening around it and adapt accordingly to minimise the risk of an accident.

BMW X3 2024 (prototype)

BMW X3 2025 prototype, motorbike detection system

Another exercise involves parking and turning across a lane. Whether or not you signal, the X3 2025's sensors and radars are able to monitor the area ahead and, if you start the manoeuvre and a car or motorbike comes up in front, it instantly stops the vehicle to avoid a collision.

At the rear, the BMW X3 2025 is also equipped with two short-range radars. These are intended to work in conjunction with the parking assistance systems, but we were able to test a very interesting function. If we are driving at low speed and our BMW X3 2025 detects another car approaching from behind at a higher speed, it is able to switch on the warning lights so that they come on more quickly as the distance reduces to alert the driver to the presence of the vehicle behind.

In every test, the BMW X3 2025 braked with great precision, stopping without false alarm and whenever necessary. New radars, cameras and sensors help avoid collisions and accidents by controlling the car from 360 degrees.

BMW X3 2025 (prototype)

BMW X3 X50i xDrive M Performance: Do you really want an X3 M?

It's time to take to the twisty track to test the X50i xDrive M Performance version, which develops around 400 PS (exact power has not yet been confirmed). Despite the camouflage, the bumpers look slightly larger, with a front splitter to improve aerodynamics. The car is also fitted with 20-inch wheels (up to 21 inches as an option), Continental SportContact 7 sports tyres and four huge tailpipes at the rear.

On the move, the sound of the twin-turbo six-cylinder engine never hides its sporty character, with a harmonious metallic melody. As for the main differences in this version, we can highlight the wheels with a specific design, modifications to the suspension with specific adaptive dampers, thicker anti-roll bars, different suspension and steering bushes, modified suspension arms, steering adjustments, chassis reinforcements and an electronically controlled sports rear differential.

During the test, the engineer who accompanied me modified the various steering and suspension settings. In Comfort mode, the X3 2025 is a comfortable car, with a family approach, where everything happens calmly and allows relaxed driving.

BMW X3 2024 test (prototype)

Prototype BMW X3 2025 - behind the wheel

But in its sportiest mode, the BMW X3 M50i xDrive M Performance is literally transformed into a sports car, with its acceleration, its approach to tight bends and its ability to link curves by changing weight in exemplary fashion. Not to mention the noise made by the six-cylinder engine as it revs up and the way the ZF torque converter gearbox is able to engage gears at almost full throttle and at such speed that there is no loss of power or thrust from one gear to the next.

Not to mention the rear differential, which allows the car to be positioned in every corner simply by pointing the steering wheel in the desired direction and giving it some throttle. It's a sum of factors that produces a marvellous result. Do you really need an X3 M with more than 500 PS when you have this?

BMW X3 2024 (prototype)

And given the versatility of this BMW X3 M50i xDrive M Performance, how about testing it off-road? Well, here we go, a rough track to check how the suspension works, a descent to activate the HDC which can operate between 2 and 18 mph and we finish the off-road test, with a loose gravel ramp with a gradient of 27% and an incline of 50%.

Here, not only do we climb the slope with ease, but we also stop in the middle of the climb, starting from a standstill to see how the xDrive all-wheel drive system is still one of the best all-wheel drive systems on the market today. I can assure you that the way it pulls without losing any traction on such slippery terrain is impressive.

BMW X3 2025 (prototype)

BMW X3 2025 PHEV: over 60 miles of electric range

Last test before returning home, I climb into the plug-in hybrid version of the BMW X3 2025 and, with an engineer, we set off on an off-site mountain road.

We don't have much information on the X3 2025 Plug-in Hybrid. For now, we know that it will be equipped with a 2.0-litre four-cylinder petrol engine and a larger battery. Thanks to the latter, optimised fuel consumption and aerodynamic improvements (Cx of 0.27), the new X3 plug-in hybrid should have an electric range of over 60 miles.

I can't confirm this, but when I started it up, with less than a quarter of the battery, the indicator showed 23 kilometres (14 miles). The indicator is divided into four parts, so if we multiply 23 by 4, we get a total of 92 kilometres of range, so it would be possible to exceed 100 kilometres (62 miles), with a leisurely drive.

During the test, the engineer changed the adaptive suspension settings. In Comfort mode, we noticed that the compression and decompression of the shock absorber were smoother, perfectly containing the rebound when the suspension was compressed with force. In this mode, although the body moves widely, it is never excessive. It also feels light in tight corners at high speeds.

BMW X3 2025 (prototype)

In Sport mode, the change is substantial, with the bodywork offering little movement, even when under load in tight bends. In this mode, the ride quality is surprisingly good, because although the dampers stiffen, they absorb the shocks without transmitting any sudden movements inside the car.

The aim of a suspension is to keep the wheels in contact with the ground, whatever the roughness of the road, without changing trajectory, whether the road is soft or hard. The work done on this aspect in the new BMW X3 is truly remarkable.

BMW X3 2025 PHEV: when will it go on sale?

The BMW X3 2025 is still a few months away from being revealed without camouflage. In June, the first images should arrive, along with the range of engines. In October, the first reservations can be made, and by the end of the year, the cars will be available from dealers across Europe.

Gallery: BMW X3 2025 test (prototype)