2008 Mercedes-Benz E550

The 2008 Mercedes-Benz E550 is a luxury sedan known for its powerful V8 engine, comfortable ride, and elegant styling. Other engine options for the W211 E-Class include various V6 and diesel engines. The E550 boasts a 5.5L V8 engine producing 382 horsepower and 391 lb-ft of torque. Owners often praise the car’s smooth acceleration, luxurious interior, and advanced features for its time. Some common complaints revolve around the higher maintenance costs associated with a luxury vehicle, especially electrical and air suspension components.

Engine

5.5L M273 V8

• Camshaft Adjuster Plugs Leaking
  • Description/Symptoms: Oil leaks from the front of the engine, specifically from the camshaft adjuster plugs located on the cylinder heads. This can lead to low oil levels and potential engine damage if left unaddressed.
  • Solution: Replacement of the camshaft adjuster plugs with updated versions.
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found
• Valve Cover Gasket Leaks
  • Description/Symptoms: Oil leaks from the valve cover gaskets, resulting in burning oil smell and potential oil dripping onto exhaust components.
  • Solution: Replacement of the valve cover gaskets.
  • Estimated Cost to Fix: $400 - $800+
  • Recalls: None Found
• Oil Filter Housing Gasket Leak
  • Description/Symptoms: Oil leaking from the oil filter housing area.
  • Solution: Replacement of the oil filter housing gasket.
  • Estimated Cost to Fix: $300 - $600
  • Recalls: None Found

Transmission

7G-Tronic 722.9 7-Speed Automatic

• Conductor Plate Failure
  • Description/Symptoms: Erratic shifting, getting stuck in a gear, limp mode, or failure to shift at all. Diagnostic Trouble Codes (DTCs) related to transmission sensors or valve body malfunctions are usually present.
  • Solution: Replacement of the conductor plate and potentially the valve body.
  • Estimated Cost to Fix: $800 - $2000+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, especially during light acceleration. Can also manifest as unusual noises coming from the transmission area.
  • Solution: Replacement of the torque converter.
  • Estimated Cost to Fix: $1500 - $3000+
  • Recalls: None Found

Suspension

• Airmatic Air Suspension Failure
  • Description/Symptoms: Vehicle sagging on one or more corners, failure of the air compressor, “Visit Workshop” message related to the suspension, harsh ride quality.
  • Solution: Replacement of the affected air struts, air compressor, or valve block.
  • Estimated Cost to Fix: $800 - $2000+ per strut, $600 - $1200+ for the compressor
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not being recognized, inability to start the car, steering lock malfunction.
  • Solution: Replacement of the EIS unit and potentially reprogramming.
  • Estimated Cost to Fix: $800 - $1500+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Various electrical malfunctions, such as non-functional lights, wipers, or other electronic components. The SAM modules control various electrical functions and can fail due to water intrusion or electrical overload.
  • Solution: Replacement and reprogramming of the faulty SAM module.
  • Estimated Cost to Fix: $500 - $1200+
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: The car’s battery drains quickly, especially when parked for extended periods.
  • Solution: Diagnosis and repair of the parasitic drain, which could be caused by faulty modules, wiring issues, or aftermarket accessories.
  • Estimated Cost to Fix: $100 - $500+ (diagnosis) + cost of repairing the faulty component
  • Recalls: None Found

Exterior

• Headlight Condensation
  • Description/Symptoms: Moisture buildup inside the headlight housings.
  • Solution: Replacement of the headlight assembly or resealing the existing housing.
  • Estimated Cost to Fix: $500-$1500+ per headlight
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, making excessive noise, or getting stuck.
  • Solution: Lubrication of the sunroof tracks, repair of the sunroof motor, or replacement of the sunroof assembly.
  • Estimated Cost to Fix: $200 - $1000+
  • Recalls: None Found

Summary

The 2008 Mercedes-Benz E550, while a luxurious and powerful vehicle, can be prone to certain issues, particularly with its engine, transmission, air suspension, and electrical systems. While some issues like valve cover gasket leaks are relatively minor, others such as conductor plate failure or Airmatic malfunctions can be quite expensive to repair. Potential buyers should be aware of these potential problems and factor in the cost of maintenance when considering purchasing this vehicle. Pre-purchase inspections are highly recommended.