2008 Mercedes-Benz E500

The 2008 Mercedes-Benz E500 is a luxury sedan that offers a blend of performance and comfort. The E500 is equipped with a 5.5-liter V8 engine producing 382 horsepower and 391 lb-ft of torque. Other engine options include the E350 which has a 3.5-liter V6, and the E63 AMG, which has a 6.2-liter V8. Transmission options primarily consist of a 7-speed automatic. Owners often praise the E500 for its smooth ride, powerful engine, and luxurious interior. Common complaints revolve around higher maintenance costs and potential electrical issues.

Engine

5.5L V8 (M273)

• Oil Leaks
  • Description/Symptoms: Oil leaks from the valve cover gaskets, oil filter housing gasket, or front timing cover. These leaks can drip onto the exhaust, causing a burning smell and potential engine bay fires. Oil puddles may form under the car when parked.
  • Solution: Replace the leaking gaskets with updated versions. Ensure proper torque during installation. Thoroughly clean any oil residue from the engine.
  • Estimated Cost to Fix: $200 - $800+ depending on the location and severity of the leak and what parts are involved.
  • Recalls: None Found
• Camshaft Adjuster Solenoid (Cam Magnet) Leaks
  • Description/Symptoms: Oil leaks from the camshaft adjuster solenoid (also known as cam magnets). Oil can wick into the engine wiring harness, potentially damaging the ECU.
  • Solution: Replace the camshaft adjuster solenoids with updated parts and install “oil stop” harness connectors to prevent oil from wicking further into the harness. Clean the affected wiring harness sections.
  • Estimated Cost to Fix: $300 - $700+
  • Recalls: None Found

Transmission

7-Speed Automatic (7G-Tronic 722.9)

• Valve Body Issues
  • Description/Symptoms: Harsh or delayed shifting, slipping between gears, or complete loss of gear engagement. Can be accompanied by diagnostic trouble codes (DTCs) related to valve body performance.
  • Solution: Replace or rebuild the valve body. In some cases, only specific solenoids within the valve body may need replacement. Perform a transmission adaptation reset after repairs.
  • Estimated Cost to Fix: $800 - $2500+
  • Recalls: None Found
• Conductor Plate Failure
  • Description/Symptoms: Transmission stuck in limp mode, inability to shift gears, or erratic shifting behavior. May trigger DTCs related to speed sensors or valve body communication.
  • Solution: Replace the conductor plate within the transmission. This involves dropping the transmission pan and valve body. Requires coding the new conductor plate to the vehicle.
  • Estimated Cost to Fix: $800 - $1800+
  • Recalls: None Found

Suspension

• Airmatic Suspension Issues (If Equipped)
  • Description/Symptoms: Vehicle sagging on one or more corners, failure of the air compressor, “Visit Workshop” warning light for the suspension system, and uneven ride height.
  • Solution: Replace the faulty air struts, air compressor, or air lines. Check and replace the air suspension relay. Ensure proper calibration of the system after repairs.
  • Estimated Cost to Fix: $800 - $2000+ per strut and $500-$1200+ for the compressor.
  • Recalls: None Found
• Ball Joint Failure
  • Description/Symptoms: Clunking or rattling noises from the front suspension, especially when going over bumps. Excessive tire wear or instability in steering.
  • Solution: Replace the worn ball joints, either as part of the control arm assembly or individually (depending on the design). Perform a wheel alignment after repairs.
  • Estimated Cost to Fix: $300 - $800+ per side.
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, inability to start the car, steering wheel lock malfunction, or intermittent electrical issues.
  • Solution: Replace the EIS unit and program it to the vehicle. This typically requires specialized diagnostic equipment.
  • Estimated Cost to Fix: $800 - $2000+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Various electrical malfunctions, such as non-functioning lights, wipers, or power windows. Diagnostic trouble codes related to communication errors within the electrical system.
  • Solution: Replace the faulty SAM unit and program it to the vehicle. This typically requires specialized diagnostic equipment. There are multiple SAM locations (Front, Rear). The symptoms will depend on which SAM is failing.
  • Estimated Cost to Fix: $500 - $1500+
  • Recalls: None Found

Exterior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, unusual noises during operation, or water leaks.
  • Solution: Clean and lubricate the sunroof tracks and mechanism. Replace any broken or worn components, such as cables or guides. Repair or replace the sunroof seal to address leaks.
  • Estimated Cost to Fix: $200 - $1000+
  • Recalls: None Found

Interior

• Center Console Display Issues
  • Description/Symptoms: Display flickering, going blank, or malfunctioning.
  • Solution: Replace or repair the center console display unit. Check the wiring connections for any loose or damaged wires.
  • Estimated Cost to Fix: $500 - $1500+
  • Recalls: None Found

Summary

The 2008 Mercedes-Benz E500 can be a rewarding vehicle to own, but potential buyers should be aware of the common issues outlined above. Engine oil leaks, transmission valve body issues, and airmatic suspension problems (if equipped) tend to be among the most costly repairs. Electrical problems, particularly with the EIS and SAM modules, can also be expensive to address. The severity of these issues can range from minor inconveniences to major mechanical failures. Preventative maintenance and careful inspection of the vehicle’s service history can help mitigate some of these risks. Overall, the E500 has medium-to-high maintenance costs compared to non-luxury vehicles.