Mercedes-Benz A 180 d
Renault-based small diesel, new generation. Economical with SCR catalyst, but still with little power reserve. Automatic only.
Diesel Everyday Without Stress
85 kW and DCT in the W177: comfortable and economical — a sensible choice for pragmatic high-mileage drivers.
Engine Weaknesses 5
Like its Renault counterpart, the OM608 uses a timing belt. Prescribed change every 120,000 km or 6 years -- frequently forgotten as Mercedes buyers are accustomed to timing chains.
Symptoms: No warning on snap -- sudden engine failure and severe engine damage
The OM608 (Renault K9K base) uses a timing belt. Mercedes specifies 200,000 km change interval; Renault prescribes 120,000 km for the same engine. A snap causes immediate total damage on this interference engine.
Symptoms: No noticeable warning before snap; beforehand: faint squealing, occasionally starting difficulties
The Renault-based OM608 1.5 CDI sometimes shows increased oil consumption from early on due to a leaking turbocharger shaft seal. Oil mist in the intake tract behind the turbo.
Symptoms: Dropping oil level, oil mist or blue smoke from exhaust, oil in air filter housing behind turbo
As a Renault K9K derivative, the OM608 shares the known EGR valve weakness. With frequent short-trip use, soot particles accumulate, the valve seizes and triggers limp mode.
Symptoms: Engine warning light, power loss, limp mode at around 3000 rpm, increased fuel consumption
With predominantly short-trip use, the OM608 is prone to DPF blockage. Regeneration intervals shorten until active regeneration is no longer sufficient and the filter must be manually regenerated or replaced.
Symptoms: DPF warning light, frequent active regeneration, fuel dilution in oil, power loss
Vehicle Weaknesses 7
On 135,454 A-Class W177 vehicles (production Sept. 2017 – Feb. 2019) the A/C condensate drain hose was not correctly routed. Condensation water could enter the footwell and cause short circuits.
On A-Class W177 with DCT gearbox from the production period January 2018 to March 2020, the gearbox may have been underfilled with oil. Consequence: possible drivetrain failure and increased fire risk.
Defective A/C connections can lead to fire risk. A recall was issued. Affected vehicles should be checked for completion of the recall.
The dual clutch gearbox in the W177 exhibits juddering and rough pull-away between 1,500–2,000 RPM. At high mileages and in urban use the clutch packs wear prematurely. Software updates alleviate the problem but do not resolve it permanently.
The MBUX infotainment system freezes or restarts spontaneously. Navigation, Bluetooth and voice control fail. Software updates usually only temporarily resolve the problem.
The MBUX system in the W177 shows sporadic issues in practice: frozen screen, incorrect traffic sign recognition and Bluetooth connection drops. Software updates are needed; on older vehicles problems are persistent.
Due to the high quiescent current draw of the numerous control units and driver assistance systems in the W177, the starter battery is particularly at risk during short-distance use and seasonally operated vehicles.
Reports & Tests
71 owner complaints filed with NHTSA (2018–2025). Most reported: Electrical (24), Other (20), Engine (14).