Mercedes Classe B W246 (2011 – 2018)

Reliability score : 8.2/10

The Mercedes-Benz B-Class (W246) represents a significant evolutionary leap from its predecessor (W245). By abandoning the expensive and heavy 'sandwich floor' architecture, Mercedes lowered the center of gravity, vastly improving driving dynamics, interior packaging, and seating position. Positioned as a premium compact MPV (Multi-Purpose Vehicle), it shares its MFA (Modular Front Architecture) platform with the A-Class (W176), CLA, and GLA. A mid-cycle facelift was introduced in late 2014 (Model Year 2015), bringing updated styling, improved infotainment (8-inch screen), and revised engine designations (e.g., 'CDI' became 'd'). While this report focuses heavily on the highly popular diesel variants, the W246 offered a remarkably diverse powertrain lineup, including petrol, natural gas, a

✅ Strengths

Excellent interior space and practicality for its footprint
High-quality cabin materials, especially post-facelift (2015+)
OM607 (1.5d) engine is incredibly fuel-efficient and cheap to run
Strong safety credentials and advanced driver assistance systems
Comfortable ride quality (avoid the optional AMG sport suspension for best comfort)

⚠️ Weaknesses

7G-DCT dual-clutch transmission can be jerky at low speeds and is expensive to repair if neglected
OM651 diesel engine timing chain is located at the rear (firewall side), making replacement highly labor-intensive
Firm ride on models equipped with AMG Line suspension and 18-inch wheels
B 250 e (Electric) suffers from severe, expensive drivetrain reliability issues
Infotainment system (NTG 4.5) on pre-facelift models feels very dated today

🎯 Verdict

The Mercedes-Benz B-Class W246 is a highly competent, premium family car that shines in practicality and safety. For diesel buyers, the choice is clear: if you drive mostly in the city or suburbs, the Renault-sourced 1.5L (OM607 / B 180 d) is the smartest, most reliable, and most economical choice, provided you change the timing belt on schedule. If you are a high-mileage highway driver, the 2.1L (OM651 / B 200 d / B 220 d) offers effortless cruising, but you must budget for a potential timing chain replacement around 150,000 - 200,000 km. Regardless of the engine, the 7G-DCT automatic transmission is the car's Achilles' heel if not meticulously maintained. Buy only with a flawless, documented service history.