"Is the Cls 350d reliable, and what should you check?"
When buying a used 2014 Mercedes-Benz CLS 350d (218), the most frequently mentioned issue is oil leaks and consumption. Clogged Diesel Particulate Filter (DPF) is also commonly reported.
Engine: OM642
OM642.858 · diesel · 350d · Used in this car from 2014-2014
Strengths
High service life with proper maintenance
Provides excellent vehicle dynamics
Watch-outs
Intake swirl flaps jam
Oil leaks quite common
Short-lived membrane of crankcase ventilation valve
Known engine issues
Oil cooler leaksThe most known problem of this diesel is oil cooler gasket leaks. Since the cooler is located in the V of the engine, replacing the cheap gaskets is expensive. Around 2010 the design was revised and such leaks no longer occur.
Fuel system issuesThe engine uses a reliable Bosch Common Rail fuel system, but its piezo injectors are very sensitive to fuel quality and expensive. Also, regular failures of the fuel quantity control valve in the high-pressure pump are noted.
Swirl flap problemsThe intake manifold has steel swirl flaps, but they are actuated by a servo with plastic rods that often break. The problem is worsened by intake clogging due to a weak crankcase ventilation membrane.
Listed from most frequently reported, each with its source.
Oil leaks and consumption
Often reported
The OM642 engine may develop oil leaks from gaskets, oil cooler, or other seals in the V6 valley area. Undetected leaks can contaminate the intercooler and manifolds, and if left unresolved, can lead to incorrect oil level and risk of mechanical damage.
Engine Internal
Clogged Diesel Particulate Filter (DPF)
Often reported
Frequent DPF clogging is reported on 3.0 V6 (OM642) engines, especially with city or short-distance driving.
Exhaust Emissions
Clogged EGR valve
Often reported
The EGR valve and associated passages are prone to carbon buildup, especially in city driving; this can cause the check engine light, torque irregularities, reduced performance, and error messages.
Exhaust Emissions
Turbocharger failures
Often reported
Reported turbocharger failures include abnormal whistling, power loss, and fault codes due to oil leaks, impeller wear, or actuator/wastegate issues. Often requires repair or replacement after high mileage or irregular maintenance.
Turbo
Mercedes-Benz Cls 350d technical specs
Mercedes-Benz Cls 350d (2014): boot 590 L; fuel use 6,4 l/100 km (urban 7,4 l/100 km · extra-urban 5,9 l/100 km); 0–100 in 6.5 s.
Boot capacity
590 L
Fuel consumption
6,4 l/100 km (urban 7,4 l/100 km · extra-urban 5,9 l/100 km)
What should I look for when buying a Mercedes-Benz CLS 350d?+
When buying a 2014 350d, check the service history, test drive, and look for engine/transmission warnings. Most commonly reported issues: oil leaks and consumption; clogged Diesel Particulate Filter (DPF); clogged EGR valve.
What are the common problems of the Mercedes-Benz CLS 350d?+
Most frequently reported issues: oil leaks and consumption; clogged Diesel Particulate Filter (DPF); clogged EGR valve.
Is the Mercedes-Benz CLS 350d reliable?+
Rather than a simple yes or no, it's best to weigh 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 the Difetti fault database; the source vehicle is verified for brand, fuel type, 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.
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