"Is the E Serisi E400d reliable, and what should you check?"
When buying a used Mercedes-Benz E-Class E400d 2020 (213 / 238), the most frequently mentioned issue is AdBlue system / SCR unit failure. Additionally, abnormal DPF regenerations and AdBlue consumption/integration are also commonly reported.
Engines available in this year
Engine varies by trim; verify the engine code on the listing.
OM656D29SCR
diesel · E400d · E 400d (330 bg) 4MATIC 9G-TRONIC
OM656.929
diesel · E400d · E 400d (340 bg) 4MATIC 9G-TRONIC
Known issues and risks
Listed from most frequently reported, each with its source.
AdBlue system / SCR unit failure
Often reported
Owners report exhaust after-treatment system (SCR unit / AdBlue dosing) faults; replacement of AdBlue system components and urea injectors is required.
Exhaust Emissions
Abnormal DPF regenerations and AdBlue consumption/integration
Often reported
Some users report higher than expected DPF regeneration frequency and excessive AdBlue consumption, leading to repeated service visits.
Exhaust Emissions
NOx sensor faults (risks for DPF/SCR)
Often reported
Faults in NOx sensors can cause warning messages, incorrect AdBlue dosing, and in prolonged cases, clogging of the DPF/SCR system.
What should I look for when buying a Mercedes-Benz E-Class E400d?+
When buying a 2020 E400d, check the service history, test drive, and engine/transmission warnings. The most commonly reported issues: AdBlue system / SCR unit failure; abnormal DPF regenerations and AdBlue consumption/integration; NOx sensor faults (risks for DPF/SCR).
What are the chronic problems of the Mercedes-Benz E-Class E400d?+
The most commonly reported issues: AdBlue system / SCR unit failure; abnormal DPF regenerations and AdBlue consumption/integration; NOx sensor faults (risks for DPF/SCR).
Is the Mercedes-Benz E-Class E400d reliable?+
Rather than a simple yes/no, it's best to weigh the proven pros and cons together. This page lists 3 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from the Difetti fault database; the source vehicle is verified for brand, fuel, engine, and generation match with the target vehicle. Topics with insufficient evidence are not shown.
We only publish claims we can verify. Cards come from Difetti fault records matched to this vehicle on brand, fuel, engine and generation.
Looking at another car?
Pick make, model and year — see the report in about 30 seconds.