2014 — 2017
4.7L M278 V8 Twin-Turbo - S550/S500 flagship saloon
Petrol
Gently accelerate and decelerate at lower speeds to feel if the 7G-Tronic transmission shifts smoothly without hesitation or clunking, as these gearboxes benefit from regular fluid flushes.
Cycling through the Airmatic suspension settings while parked to ensure the vehicle levels out promptly without any audible groaning or compressor rattles.
Listen for any faint ticking or rattling during a cold start, as the M278 engine is known to occasionally develop timing chain tensioner wear which is worth monitoring as part of your service schedule.
Check for any signs of dampness in the front footwells or boot electronics compartments, as clogged sunroof or body drains can sometimes allow water ingress in older prestige saloons.
Usually marks the point where the Airmatic suspension components and engine mounts may begin to show their age.
The typical interval for a major transmission service and potentially checking the cooling system plastic connectors for signs of aging.
Often the time to inspect auxiliary drive belts, pulleys, and the water pump for proactive replacement.
Check for any outstanding manufacturer recalls by entering the VIN into the official Mercedes-Benz NZ portal.
Prioritize a full pre-purchase inspection from an independent specialist familiar with the W222 chassis.
Ensure the digital service history is complete and verified, ideally showing oil changes every 10,000 to 15,000km.
Verify the condition of the tires and brakes, as these premium components are specific to the S-Class and represent a significant part of the running costs.
Test every interior electronic function, from the soft-close doors to the seat massage features, as these convenience systems are complex.
Estimated repair costs if issues arise
In cars of this age, the air bags or the compressor may eventually need refurbishment. If this component needs attention in the future, it is a standard part of owning a flagship saloon with adjustable ride height.
While not a guaranteed failure, it is common to consider the condition of the timing drive as the vehicle ages. Depending on the car's history, you might eventually need to budget for a check or proactive maintenance to keep the V8 running quietly.
The M278 engine produces significant torque, and the mounts naturally wear over time. If you notice increased vibration at idle, you might eventually need to budget for a refresh to restore that signature smooth S-Class driving experience.
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Disclaimer: This report is generated with the assistance of AI analysis based on verified automotive data. While we strive for 100% accuracy, enthusiasts should always conduct physical inspections and consult service records. View Full Disclaimer