Mercedes Classe B W246 (2011 – 2018)

Reliability score : 8.2/10

The second-generation Mercedes-Benz B-Class (codename W246) marks a complete break with its predecessor (W245). Gone is the complex and costly sandwich floor: the W246 is based on the MFA (Modular Front Architecture) platform, shared with the A-Class (W176). This change lowers the center of gravity, drastically improves road handling, and allows for a more conventional but significantly more premium interior. Facelifted in late 2014 (Phase 2), it corrected its early flaws (notably the firmness of the suspension) and modernized its infotainment. On the used car market, gasoline versions (M270 engine) are particularly sought after for their superior reliability compared to diesels in urban/suburban use, and their perfect suitability for the model's family vocation.

✅ Strengths

Overall reliability of gasoline engines (M270) very reassuring
Finish quality and interior presentation significantly improved (especially Phase 2)
Generous interior space and practical trunk (optional sliding rear bench)
Safe and dynamic road handling
Standard active safety equipment (Collision Prevention Assist)

⚠️ Weaknesses

7G-DCT automatic gearbox sometimes harsh at low speeds (especially Phase 1)
Firm suspension comfort on Phase 1 models (2011-2014) and AMG Line trims
Poor rear visibility (reversing camera almost essential)
High maintenance cost in the Mercedes network for a compact MPV
Random reliability of the electric version (B 250 e)

🎯 Verdict

The Mercedes B-Class W246 is an excellent used car choice, particularly with its gasoline engines (B 180 and B 200). The M270 engine proves to be robust, quiet, and perfectly suited to the vehicle's philosophy, avoiding the DPF and EGR hassles of diesels in urban use. Opt for a facelifted model (after November 2014) to benefit from better suspension comfort, a refined finish, and a better calibrated 7G-DCT gearbox. The purchase is highly recommended under one strict condition: demand a clear service history, especially regarding the oil change for the dual-clutch automatic gearbox.

Common issues

Problèmes de la boîte de vitesses 7G-DCT (à double embrayage) High

🔧 100 000 – 180 000 km

💶 2 500 – 5 000 €

Tester la douceur des changements de vitesse à chaud et à froid.

Fuites du boîtier de thermostat ou du circuit de refroidissement Medium

🔧 80 000 – 150 000 km

💶 300 – 700 €

Vérifier régulièrement le niveau de liquide de refroidissement et les traces de fuite.

Dysfonctionnement de l'actionneur de turbo ou de la wastegate Medium

🔧 120 000 – 200 000 km

💶 800 – 1 800 €

Attention à la perte de puissance ou au bruit anormal du turbo.

Usure prématurée des supports moteur (silentblocs) Low

🔧 90 000 – 160 000 km

💶 400 – 800 €

Examiner les vibrations excessives au ralenti ou à l'accélération.

Estimated maintenance costs

Oil change	£90 – 160
Timing chain	£1 300 – 2 200
Complete brakes	£350 – 600
Estimated annual budget	£700 – 1 300

Indicative estimates (independent garage, UK market). Prices vary by region and year.