"Is the S Serisi S350 reliable, and what should you check?"
When buying a used Mercedes-Benz S-Class S350 2011 (221 / facelift), the most frequently mentioned issue is oil leaks from the oil cooler seals or V-valley seals. Also, a clogged Diesel Particulate Filter (DPF) is commonly reported.
Engines available in this year
Engine varies by trim; verify the engine code on the listing.
M276.950
turbo petrol · S350 · S 350 BlueEFFICIENCY (306 bg) G-TRONIC
Listed from most frequently reported, each with its source.
Oil leaks from oil cooler seals or V-valley seals
Often reported
On the OM642 V6 engine, oil leaks from the oil cooler seals or other seals in the V-valley are frequently reported. These leaks may require labor-intensive repairs involving removal of the intake manifolds and upper components.
Engine Internal
Clogged Diesel Particulate Filter (DPF)
Often reported
On the 3.0 V6 CDI (OM642) engine, the DPF frequently clogs, especially with city or short-distance driving.
Exhaust Emissions
Clogged EGR valve and related warning lights/faults
Often reported
On the 3.0 CDI, carbon buildup in the EGR valve is a documented issue: the valve may stick or give a signal fault, generating error codes and subsequently causing DPF clogging.
Exhaust Emissions
Turbo and intake manifold issues
Often reported
Deterioration or breakage in the intake manifold can cause turbo failures (oil leaks or impeller damage) and performance loss. Some vehicles report turbo issues after high mileage.
What should I look for when buying a Mercedes-Benz S-Class S350?+
When buying a 2011 S350, check the service history, test drive, and look for engine/transmission warnings. The most commonly reported issues are: oil leaks from oil cooler seals or V-valley seals; clogged Diesel Particulate Filter (DPF); clogged EGR valve and related warning lights/faults.
What are the chronic problems of the Mercedes-Benz S-Class S350?+
The most commonly reported issues are: oil leaks from oil cooler seals or V-valley seals; clogged Diesel Particulate Filter (DPF); clogged EGR valve and related warning lights/faults.
Is the Mercedes-Benz S-Class S350 reliable?+
Instead of a simple yes/no, it is necessary to evaluate the proven pros and cons together. This page lists 4 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from Difetti fault database records; the source vehicle and target vehicle are verified for brand, fuel, engine, and generation compatibility. Topics with insufficient evidence are not shown.