The BMW N55 is a 3.0-liter turbocharged inline-six that debuted in 2009 as the successor to the twin-turbo N54. By replacing that engine's parallel turbo setup with a single twin-scroll turbocharger and adding Valvetronic variable valve lift, BMW delivered comparable performance with improved throttle response, reduced complexity, and better efficiency. Produced through 2016, it became one of BMW's most widely deployed modern sixes.
Engineering & Specs
The N55 pairs High Precision Direct Injection with a single twin-scroll turbo, Double-VANOS, and Valvetronic throttle-less intake control. Output ranged from 300 to 365 horsepower and 300 to 369 lb-ft of torque depending on application, with a 7000 rpm redline.
- Configuration: 3.0L single-turbo inline-six
- Induction: Single twin-scroll turbocharger
- Output: 300–365 hp / 300–369 lb-ft
- Redline: 7000 rpm
- Production: 2009–2016
Unlike BMW's V8 and V12 turbo efforts such as the N63 and the naturally aspirated N62, the N55 concentrated its TwinPower philosophy into a compact, high-revving six.
Which BMWs Used It
The N55 saw broad service across the BMW lineup:
- 335i (F30 and E9x variants)
- 535i
- X3, X4, and X5 35i models
- M235i
- F87 M2 — the first M2
Powering the debut M2 cemented the N55's enthusiast credibility. Not sure which six is under your hood? Run your VIN through our VIN decoder to confirm the exact engine fitted to your car.
Reliability & Ownership Notes
The N55 is generally regarded as more robust than the earlier N54, largely because the single turbo removed a duplicate set of failure points. Owners should still budget for common maintenance items:
- Valve cover and oil filter housing gaskets that can weep over time
- Water pump and thermostat wear on higher-mileage cars
- Carbon buildup on intake valves, inherent to direct injection
- Charge pipe upgrades often desired on tuned examples
When shopping, prioritize documented cooling-system service and consistent oil changes. The N55 responds exceptionally well to tuning, so verify whether a used example has been modified and whether that work was done responsibly.
Legacy
The N55 represented a pivotal shift in BMW's turbocharging strategy, proving that a single well-engineered turbo could match a twin-turbo predecessor while simplifying the package. Its role in the F87 M2 secured its place in enthusiast history. Explore how it fits within BMW's broader engine family in our BMW DNA encyclopedia, alongside flagship powerplants like the N74.