The Second Wave of Diesel Introductions in Japan

Volvo's diesel introduction signifies the beginning of the second wave of diesel vehicle introductions by European brands in Japan.

Following Volvo, Volkswagen Japan recently announced that it will add a diesel model to thenew Passatby the end of this year. Audi Japan, part of the same group, has also announced plans to equip multiple models with diesel engines early next year. Jaguar Land Rover Japan has decided to add diesel to its brand-new model,Jaguar XEas well. Additionally, Peugeot Citroën Japon will unveil the diesel "508" at this autumn's Tokyo Motor Show and plans to launch it in Japan early next year. Its engine is expected to be fitted into the popular308early next year.

The diesel engine scandal involving VW has cast a shadow, and regardless of the truth, a temporary distrust of diesel engines across all manufacturers is unavoidable. However, in the long run, diesel engines will continue to hold their ground as a viable solution, and in Japan, a laggard in diesel adoption, their proportion is expected to increase, primarily among imported cars, in the medium term.



Following BMW (including theMini) and Mercedes-Benz, which already sell 4-cylinder diesels in Japan, why has there been such a sudden influx of introductions?

There are two reasons. Firstly, European emission regulations, which have been progressively tightened, have approached the notoriously strict Japanese standards, making it possible to prepare Japanese specifications without incurring massive costs. Secondly, in response to Mazda's success in revitalizing the diesel market in Japan with its wide range of diesel models over the past few years, European manufacturers have recognized this as a business opportunity.

As a result, Japan can finally choose from a diverse array of diesel models. For those who have patiently waited for their favorite European brands to offer diesel options, the wait is almost over. For those who couldn't wait and bought gasoline models, modern direct-injection turbocharged gasoline engines offer power comparable to diesels, so there's no need for despair. And for those who imported diesel models impatiently, you could have bought them cheaper with the strong yen.

Comparison with Rivals

Now, about Volvo's diesels. All models share the same specifications: a maximum output of 190ps/4250rpm and a peak torque of 40.8kgm/1750-2500rpm. For reference, let's briefly look at the specifications of 2-liter inline-4 turbo diesels from various manufacturers.

—BMW Longitudinal (3 Series, 5 Series, X3)
Maximum output 184ps/4,000rpm, peak torque 38.7kgm/1,750-2,750rpm
—BMW Transverse (2 Series Active Tourer)
Maximum output 150ps/4,000rpm, peak torque 33.7kgm/1,750-2,750rpm
—Mini Cooper SD (Crossover, Paceman)
Maximum output 143ps/4,000rpm, peak torque 31.1kgm/1,750-2,700rpm
—Mini Cooper D (Paceman)
Maximum output 112ps/4,000rpm, peak torque 27.5kgm/1,500-2,500rpm
—Jaguar XE (planned specifications)
Maximum output 180ps/4,000rpm, peak torque 43.8kgm/1,750-2,500rpm
(Specifications for VW, Audi, and Peugeot diesel models for the Japanese market have not yet been clarified.)



Let's also look at the specifications of 4-cylinder diesels other than 2-liter ones currently available in Japan.

<1.5-liter>
—Mazda SKYACTIV-D (Demio)
Maximum output 105ps/4,000rpm, peak torque 25.5kgm/1,500-2,500rpm

<2.2-liter>
—Mercedes-Benz (E, CLS)
Maximum output 177ps/3,200-3,800rpm, peak torque 40.8kgm/1,400-2,800rpm
—Mazda SKYACTIV-D (Atenza, Axela, CX-5)
Maximum output 175ps/4,500rpm, peak torque 42.8kgm/2,000rpm

<2.3-liter>
—Mitsubishi (Delica D:5)
Maximum output 148ps/3,500rpm, peak torque 36.7kgm/1,500-2,750rpm

<2.8-liter>
—Toyota (Land Cruiser Prado)
Maximum output 177ps/3,400rpm, 45.9kgm/1,600-2,400rpm



Looking at these figures, the D4's peak torque of 40.8kgm is average for a 2-liter turbo diesel, while its maximum output of 190ps is quite high.

Ample Power and Eco-Friendly Performance

However, specifications are just numbers. Without driving it, one cannot truly know its actual or perceived speed and power.

The first model I test drove was the XC60. Outside the car, the engine noise, characterized by the distinct diesel "clatter," was noticeable, though not unpleasantly loud. However, once the door was opened, the interior became remarkably quiet with minimal vibration. The sound insulation and vibration damping measures were clearly effective. For instance, the engine's head cover, typically a plastic panel fixed above the head, was a thick, soft, sponge-like material attached to the head.



Once on the move, the noise and vibration became even less noticeable, to the point where a passenger might not realize it's a diesel if not told. The driver, however, would likely recognize its power immediately. Abundant torque is available from low RPMs, and the 8-speed automatic transmission efficiently shifts gears with minimal shock, allowing the car to reach desired speeds quickly. While high-revving gasoline engines in sports cars offer a dramatic ascent through the RPM range to be enjoyed, the latest turbo diesels bypass this, accelerating swiftly.

While emphasizing the "power" of diesel engines, having ample power also means the potential for better fuel economy when not driven aggressively. Volvo models equipped with the D4 engine feature an "Eco+" mode. Selecting this mode optimizes gear shifts and lock-up points, and softens the accelerator pedal response (while also increasing pedal travel).

Anticipating the Arrival of AWD Models

The addition of a powerful and efficient powertrain has undoubtedly enhanced the overall capabilities of the XC60, which already boasted a comfortable ride and competent handling. The only disappointment is that the diesel is only available with front-wheel drive. For a diesel model that truly shines on long journeys, the ability to combine it with all-wheel drive would allow for worry-free travel regardless of season, weather, or road conditions.

In addition to the XC60, I also test drove the D4-equipped S60, V40, and V40 Cross Country models. While the lighter V40 series doesn't feel significantly faster despite using the same engine, its lighter weight contributes to better fuel economy: 20.0 km/ℓ for the V40 and 21.2 km/ℓ for the V40 Cross Country, compared to the XC60's 18.6 km/ℓ. Incidentally, the V40 Cross Country achieves 1.2 km/ℓ better fuel economy than the V40, despite being 10 kg heavier; this is purely coincidental. For imported cars, where measurement accuracy may not be as rigorously pursued as with domestic models, such discrepancies can occasionally occur.



Volvo has priced its diesel models slightly lower than comparable trims with similar equipment from rival manufacturers. Just a few years ago, simply having a "diesel model" was a significant differentiator. However, as diesel models become available across many brands, we are entering an era where direct comparisons between diesel cars will be common.

What can be said at this stage is that while there's no need to rush, if you test drive a diesel Volvo and like it, there's no need to wait for other brands to release their models. For those in colder regions or who enjoy winter sports, patience may be required until diesel 4WD versions become available.

Volvo V40 D4 SE | Volvo V40 D4 SE
Body Dimensions | Length 4,370 × Width 1,800 × Height 1,440 mm
Wheelbase | 2,645 mm
Tread Front/Rear | 1,545/1,535 mm
Weight | 1,540 kg
Engine | 1.968 cc Inline-4 Diesel Turbo
Bore x Stroke | 82.0 × 93.2 mm
Compression Ratio | 15.8:1
Maximum Output | 140 kW (190 ps) / 4,250 rpm
Peak Torque | 400 Nm (40.8 kgm) / 1,750−2,500 rpm
Transmission | 8-speed Automatic
Drivetrain | FF
Suspension Front | MacPherson Strut
Suspension Rear | Multi-link
Brakes Front | Disc
Brakes Rear | Disc
Tires Front/Rear | 205/50R17
Fuel Economy (JC08 mode) | 20.0 km/ℓ
Price | 3,990,000 yen

Volvo S60 D4 R-Design | Volvo S60 D4 R-Design
Body Dimensions | Length 4,635 × Width 1,865 × Height 1,480 mm
Wheelbase | 2,775 mm
Tread Front/Rear | 1,580/1,575 mm
Weight | 1,620 kg
Engine | 1,968 cc Inline-4 Diesel Turbo
Bore x Stroke | 82.0 × 93.2 mm
Compression Ratio | 15.8:1
Maximum Output | 140 kW (190 ps) / 4,250 rpm
Peak Torque | 400 Nm (40.8 kgm) / 1,750−2,500 rpm
Transmission | 8-speed Automatic
Drivetrain | FF
Suspension Front | MacPherson Strut
Suspension Rear | Multi-link
Brakes Front | Disc
Brakes Rear | Disc
Tires Front/Rear | 235/40R18
Fuel Economy (JC08 mode) | 20.9 km/ℓ
Price | 5,290,000 yen

Volvo XC60 D4 SE | Volvo XC60 D4 SE
Body Dimensions | Length 4,645 × Width 1,890 × Height 1,715 mm
Wheelbase | 2,775 mm
Tread Front/Rear | 1,630/1,585 mm
Weight | 1,800 kg
Engine | 1,968 cc Inline-4 Diesel Turbo
Bore x Stroke | 82.0 × 93.2 mm
Compression Ratio | 15.8:1
Maximum Output | 140 kW (190 ps) / 4,250 rpm
Peak Torque | 400 Nm (40.8 kgm) / 1,750−2,500 rpm
Transmission | 8-speed Automatic
Drivetrain | FF
Suspension Front | MacPherson Strut
Suspension Rear | Multi-link
Brakes Front | Disc
Brakes Rear | Disc
Tires Front/Rear | 235/60R18
Fuel Economy (JC08 mode) | 18.6 km/ℓ
Price | 6,750,000 yen