CD changers, command units, voice control units, PSE units, and Tele Aid units are prone to failure, especially in early models.
Mercedes-Benz S350 Problem Reports
Newest Mercedes-Benz S350 Problem Reports
Problems with the pneumatic system can cause closing assist and door lock issues.
High mileage vehicles may develop a leak from one or more of the transmission oil seals.
A fluid leak from the front of the vehicle may be a result of a worn steering dampening shock. Our technicians tell us that if a leak is noted from the dampening shock it should be replaced.
As brake fluid becomes dirty over time, it can cause a failure of the anti-lock brake system (ABS) modulator assembly. Our technicians recommend a complete brake system flush every two years to help prevent this issue.
A cracked or broken heater core outlet housing can cause a coolant leak near the bulkhead (firewall). Our technicians remind us that coolant leaks should be repaired in order to avoid overheating the engine due to coolant loss.
One or more of the following steering linkage components may wear prematurely; tie rod ends, drag link, or idler arm. Our technicians remind us the wheel alignment should be checked and adjusted if any of these items are replaced.
Vehicles equipped with a 7-speed automatic transmission may develop a rough shifting condition, most commonly going up from first to second gear and going down from third to second or second to first gear. Our technicians tell us this is due to an internal component failure. Mercedes has released updated parts; the transmission will need to be removed and disassembled to complete the necessary repairs.
The brakes may begin to squeak at about the 50 percent wear point. This is due to the size and material used for the brake pads and rotors. The brake rotor surfaces become uneven, causing a lip to form at the outer edge. This will generally require replacement of the rotors when the pads are worn (pad life varies depending on driving style and terrain).
Leaks may develop from the differential cover and/or seals on high mileage or older vehicles. Our technicians recommend a complete reseal of the differential unit if these leaks are addressed.
The engine wiring can degrade because the insulating material falls off leaving the bare wire exposed. This can cause many problems depending on which wires are exposed and what they touch.
An engine oil leak may develop from the oil level sensor. Replacement of the leaking sensor will commonly correct this concern.
Front thrust arm and control arm bushings can crack and sometimes tear completely. If this is not repaired quickly, damage to the front subframe unit will occur, which is very expensive to repair. Updated control arms (that prevent damage to the subframe when the bushings wear out) are available.
Due to wear, high usage vehicles can experience ignition lock and tumbler failures. The ignition lock cylinder will generally require replacement to correct this concern.