The E39 520d

Engine
The engine that powered the BMW E39 520d was a 2.0-liter inline-four (I4) turbodiesel, designated as the M47D20. This engine featured a common rail direct fuel injection system, which was a significant advancement over the indirect injection systems found in older diesel engines. With a double overhead camshaft (DOHC) design and 16 valves, it delivered improved efficiency and performance. However, it is to be noted that this little diesel 4cyl is by no means fast. In fact, it is the weakest engine available on the E39, in terms of performance.
But this does not mean you should run away from the 520d. It does get an astonishingly good fuel economy and with its well-known reliability, the 520d is a perfect candidate for a daily driving, economical E39.
Performance
The M47 engine in the BMW E39 520d initially produced 136 horsepower (100 kW) at 4,000 rpm and 280 Nm of torque (207 lb-ft) at 1,750 rpm. While this output was modest compared to some of the more powerful engines in the E39 lineup, it provided a good balance between efficiency and everyday usability. The engine's torque was particularly well-suited for relaxed cruising and city driving, as it peaked at low RPMs, allowing for smooth acceleration and minimal gear changes.
Specs:
- Power Output: 136 hp (100 kW) at 4,000 rpm
- Torque: 280 Nm (207 lb-ft) at 1,750 rpm
- 0-100 km/h (0-62 mph) Acceleration: 10.6 seconds
- Top Speed: 207 km/h (129 mph)
The M47's common rail direct injection system improved fuel atomization and combustion efficiency, resulting in excellent fuel economy for its class. However, the engine's modest horsepower could feel limiting during overtaking at higher speeds, especially when the car was fully loaded.
For those seeking more power while maintaining good fuel economy, the later E39 models equipped with the updated M47TUD20 engine (150 hp) offered improved performance, as did larger diesel options like the 525d or 530d models.
Specs (150 hp version):
- Engine Type: 2.0-liter inline-four (I4) turbodiesel
- Power Output: 150 hp (110 kW) at 4,000 rpm
- Torque: 330 Nm (243 lb-ft) at 2,000 rpm
- 0-100 km/h (0-62 mph) Acceleration: 9.6 seconds
- Top Speed: 216 km/h (134 mph)
- Fuel Injection: Common rail direct injection
- Turbocharger: Variable-geometry turbocharger (VGT) for improved performance and efficiency
- Emission Standard: Euro 3 or Euro 4 (depending on the production year and market).
520d Sound
520d Acceleration
Reliability
The M47 engine was generally well-regarded for its durability when properly maintained. However, owners often reported issues with the swirl flaps in the intake manifold, which could break off and cause serious engine damage. Many enthusiasts recommend deleting or replacing these components as a precaution. Additionally, regular servicing of the turbocharger and fuel injectors was key to avoiding costly repairs. With proper care, the M47 engine was capable of covering high mileages reliably, making it a solid choice for budget-conscious buyers.
Fuel Consumption – A Standout Feature of the M47
One of the most attractive features of the M47 diesel engine in the BMW E39 520d was its exceptional fuel efficiency, making it an economical choice for buyers prioritizing lower running costs. The combination of a smaller displacement diesel engine, direct injection, and turbocharging contributed to impressive fuel economy figures, especially compared to petrol-powered variants in the E39 range.
Fuel Consumption (Combined): 5.9–6.3 liters per 100 kilometers (roughly 37–40 mpg)
Fuel Tank Capacity: 70 liters (18.5 gallons)
Market Context
The E39 520d, like the other diesel-powered E39's, was not available in the US market, where petrol engines dominated. In the UK and Europe, the 520d appealed to drivers looking for an economical alternative to petrol variants like the 520i (2.2L I6) or the 523i (2.5L I6). Its balance of luxury features and low running costs made it particularly popular in regions where diesel powertrains were highly regarded for efficiency.
In contrast, the US market for the E39 lineup was focused on larger petrol engines like the 525i (2.5L I6), 530i (3.0L I6), and the high-performance 540i (4.4L V8). The absence of diesel options meant US buyers did not benefit from the fuel efficiency of models like the 520d, leaving the European market to enjoy its cost-saving advantages.