Mercedes GLB X247 (2019 – 2025)

Reliability score : 8.4/10

The Mercedes-Benz GLB (X247) is a compact family SUV based on the MFA2 platform (shared with the A-Class and GLA). Its positioning is unique in the premium segment: it offers a cubic silhouette maximizing interior space and provides up to 7 seats (optional), placing it as a more compact alternative to the GLC and more practical than the GLA. Launched in late 2019, it received a facelift in 2023, introducing mild hybridization (MHEV 48V) on gasoline engines, an update to the MBUX infotainment system, and minor aesthetic tweaks. Although demand for gasoline is increasing, diesel engines (OM654q) remain the preferred choice for this family-oriented and road-trip vehicle, offering generous torque and controlled consumption given the vehicle's weight and aerodynamics.

✅ Strengths

Exceptional spaciousness for its size (4.63 m) and a very rare 7-seater option in this premium segment.
Particularly successful diesel engines (OM654q): economical, torquey, and quiet.
Advanced onboard technology (highly responsive MBUX dual screen).
Suspension comfort, especially with the optional adaptive damping.
Smooth and responsive 8G-DCT gearbox, well-calibrated with the diesel's torque.

⚠️ Weaknesses

Aerodynamics (cubic profile) generating wind noise on the highway above 120 km/h.
Quality of some plastics in the lower part of the cabin, unworthy of the Mercedes badge.
3rd-row seats (7-seater option) strictly reserved for children or for occasional use (max 1.68m according to Mercedes).
Very high prices, both for purchase and maintenance within the official network.
Absence of a plug-in hybrid (PHEV) powertrain.

🎯 Verdict

The Mercedes GLB (X247) is undoubtedly the most pragmatic and intelligent compact SUV in the star's lineup. By maximizing interior space on a reduced footprint, it perfectly meets the needs of families. Diesel Focus: The OM654q engine is a resounding success. It erases the flaws of the previous generation (noise, roughness) while offering remarkable fuel efficiency for a vehicle of this size. The 200 d (150 hp) version represents the ideal compromise: torquey enough to power the loaded vehicle, without the extra cost of the 220 d version. Buying Advice: Prioritize a 200 d model with a clear service history (especially for the DCT gearbox). Avoid diesel if your use is strictly urban (to preserve the DPF and AdBlue); in this case, the GLB 200 gasoline (M282) will be a more judicious choice. The 2023 facelift brings a real technological advantage, but 2021-2022 models currently offer the best value for money on the used market.

Common issues

Dysfonctionnements du système AdBlue/SCR (capteurs, pompe, chauffage) High

🔧 80 000 – 150 000 km

💶 800 – 2 000 €

Utiliser AdBlue de qualité, éviter de rouler avec un niveau bas.

Encrassement ou défaillance du Filtre à Particules (FAP/DPF) moyenne à haute

🔧 100 000 – 200 000 km

💶 1 000 – 2 500 €

Effectuer régulièrement des trajets autoroutiers pour la régénération.

Défaillance des capteurs NOx (oxydes d'azote) Medium

🔧 70 000 – 130 000 km

💶 400 – 800 €

Ne pas ignorer les voyants moteur, faire diagnostiquer rapidement.

Encrassement ou défaillance de la vanne EGR (Exhaust Gas Recirculation) Medium

🔧 100 000 – 180 000 km

💶 500 – 1 000 €

Un entretien régulier et une conduite adaptée peuvent limiter l'encrassement.

Problèmes logiciels MBUX ou électroniques mineurs (glitches, écrans figés) Low

🔧 Variable, souvent en début de vie

💶 0 – 500 €

S'assurer que le véhicule a les dernières mises à jour logicielles.

Estimated maintenance costs

Oil change	£130 – 230
Complete brakes	£350 – 700
Estimated annual budget	£750 – 1 400

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