"Is the S Serisi S680 reliable, and what should you check?"
When buying a used Mercedes-Benz S-Class S680 2026 (223), the most frequently mentioned issue is faulty thermostats and cooling circuits. Additionally, oil leaks (gaskets and seals) are also commonly reported.
Engines available in this year
Engine varies by trim; verify the engine code on the listing.
Listed from most frequently reported, each with its source.
Faulty thermostats and cooling circuits
Often reported
Multiple users report failures of thermostats or cooling circuit pipes/manifolds located in hard-to-reach areas. Replacement often requires extensive labor and may involve removing accessory components.
Cooling
Oil leaks (gaskets and seals)
Often reported
Common oil leaks on the V8 M177 architecture: deteriorated valve cover gaskets, excessive crankcase pressure due to undersized air/oil separators, and documented rear main seal leaks.
Engine Internal
Ignition, injector, and timing faults
Often reported
Reports of misfires, ignition coils and injectors needing replacement, and error codes related to the direct injection system. Users attribute many issues to high-output engines: spark plugs and coils wear quickly.
Engine Internal
Oil in turbos and turbo seals
Often reported
Multiple users report oil in the turbo housing, air filter, and under the turbo, sometimes accompanied by a burning smell.
What should I look for when buying a Mercedes-Benz S-Class S680?+
When buying a 2026 S680, check the service history, test drive, and look for engine/transmission warnings. The most commonly reported issues are: faulty thermostats and cooling circuits; oil leaks (gaskets and seals); ignition, injector, and timing faults.
What are the chronic problems of the Mercedes-Benz S-Class S680?+
The most commonly reported issues are: faulty thermostats and cooling circuits; oil leaks (gaskets and seals); ignition, injector, and timing faults.
Is the Mercedes-Benz S-Class S680 reliable?+
Rather than a simple yes/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 Difetti fault database records; the source vehicle is verified for brand, fuel, engine, and generation match with the target vehicle. Topics with insufficient evidence are not shown.