Common Mercedes Repair Issues Drivers Experience As Their Vehicle Ages

Mercedes-Benz is a constant competitor when it comes to discussing the best luxury brands. By combining high-end materials and superior craftsmanship, Mercedes models continue to be highly desirable even as they age. Buying an older Mercedes has become the go-to option for drivers looking for luxury on a more reasonable budget. Whether you’re looking at buying an older Merc, or just can't seem to part ways with your aging Bavarian, these are some of the common Mercedes repair tasks to be aware of.

Airmatic Failures

Mercedes-Benz Airmatic system is a common air-suspension system found on higher-end models such as the S-class and G-Class. Air suspension is favored over the more traditional coil and dampener design as it offers a smoother ride and adjustable ride height.

However, as your Merc ages, two major components can begin to fail. The first being rubber components such as the air struts and connecting hoses. Like all other rubber components, they have an expected life span and will begin to harden and crack, which introduces air leaks. Depending on the severity of the air leak, your vehicle may completely fail to raise its suspension level, or merely lower when the car isn’t running. The two most common repairs are either to source replacement air struts and lines or to completely replace the suspension with a coil over option.

The second point of failure often lies with the air compressor itself. In order to raise the suspension level, an air compressor is used to fill the air struts. A compressor, in its simplest form, is an electric motor attached to a compressor wheel. Electric motors are known to fail with age, but fortunately, they can be repaired by having the coil recoiled and having the coil bushings replaced.

Engine Mount Wear

Another innovation Mercedes uses to ensure a smooth ride is oil-filled engine mounts. Unlike the solid rubber variants used by most manufacturers, oil-filled engine engine mounts are far superior at isolating vibrations created by the engine.

The downside of an oil-filled engine mount is that once they begin to crack and leak, their rate of deterioration is far quicker than that of solid rubber. As soon as the oil starts leaking out, there is no method to refill them, whereas solid rubber mounts can still offer some isolation until they completely wear out or disintegrate.

Since there's no way to patch a crack or refill the mount with oil, replacing your mounts is the only recommended repair option.

Rust and Corrosion

While there are many upsides to life in South Florida, the inevitable trade we make is rust. There is simply no escaping the ocean air and high humidity levels, which can cause all kinds of havoc with your Mercedes. Body rust is common, causing unsightly bubbles in the body work, weakening core suspension components, and can get extreme enough to render a car unroadworthy.

Fortunately, rust is both repairable and preventable. Suspension components can be replaced, body panels can have corroded metal removed, replaced, and painted, and prevention is as simple as ensuring your undercarriage is cleaned with a premium auto detail and by applying a protective undercoat.

What many owners don't realize is the havoc humidity and salty air can play on electronics. Many serviceable electronic units are only sealed with a rubber gasket, and as the gasket ages and cracks, internal components can corrode, causing circuits to break and whole modules to fail.

This was far more common in models from the 90s, and for critical systems, Mercedes has attempted to rectify the issue by submerging circuit boards in resin and using more aggressive sealing techniques for serviceable modules.

Turbo Failure

As Mercedes continues to find new ways to fulfill our need for performance, more and more of their lineup is becoming Turbocharged. While Turbos are a fun and effective way to increase the performance output of any engine, they do introduce a few new failure points. The first point of failure is with the turbo itself. As the turbo ages, the tolerances become looser and looser. These looser tolerances allow for boost and oil leaks that lead to decreased performance.

The second point of failure is with the turbo actuators that control the amount of boost being delivered to the engine. When the turbo begins to produce pressure beyond a desired range, actuators are designed to open and allow excess pressure to be dumped. If these actuators get stuck closed, it can lead to an overboost condition, and if they get stuck closed, it can lead to a no boost or boost leak code.

Depending on the model, some actuators can be cleaned and resealed, certain turbos can be rebuilt, but we have always been firm believers that when it comes to Turbos, an upgrade is always better than a rebuild!