2009 Mercedes-Benz CLK550

The 2009 Mercedes-Benz CLK550 is a stylish and powerful coupe that offered a blend of luxury and performance. It came standard with a 5.5-liter V8 engine producing 382 horsepower and 391 lb-ft of torque, paired with a 7-speed automatic transmission. While praised for its elegant design, strong engine, and comfortable ride, the CLK550 can be prone to certain issues as it ages. Some owners have complained about electrical problems, suspension issues, and the cost of maintaining a high-performance vehicle. Other engine options were the CLK350 which included a 3.5L V6 engine and the CLK63 AMG which featured a 6.2L V8 engine.

Engine

5.5L M273 V8

• Camshaft Adjuster Solenoid Failure
  • Description/Symptoms: Check engine light, rough idling, decreased fuel economy, and potential misfires. The engine might make rattling noises on startup or have reduced power.
  • Solution: Replace the faulty camshaft adjuster solenoid(s).
  • Estimated Cost to Fix: $300 - $800+, depending on the mechanic and which solenoid needs replacement.
  • Recalls: None Found
• Oil Leaks (Valve Cover Gaskets, Oil Filter Housing)
  • Description/Symptoms: Visible oil leaks on the engine, burning oil smell, low oil level warning, and potential smoke from the engine bay.
  • Solution: Replace the leaking gaskets or seals.
  • Estimated Cost to Fix: Valve cover gaskets: $200 - $500. Oil filter housing: $300 - $700.
  • Recalls: None Found

Transmission

7G-Tronic (722.9) 7-Speed Automatic

• Torque Converter Issues
  • Description/Symptoms: Shuddering or vibration during acceleration, particularly at lower speeds. Erratic shifting and possible stalling.
  • Solution: Torque converter replacement.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Valve Body Failure
  • Description/Symptoms: Harsh or delayed shifting, transmission slipping, getting stuck in a gear, or failing to shift at all.
  • Solution: Replace or rebuild the valve body.
  • Estimated Cost to Fix: $800 - $2,000+
  • Recalls: None Found

Suspension

• Airmatic Suspension Problems (If Equipped)
  • Description/Symptoms: Vehicle sagging on one or more corners, failure to maintain proper ride height, Airmatic malfunction warning light, and noise from the air compressor.
  • Solution: Replace leaking air struts, repair or replace the air compressor, or address issues with the valve block.
  • Estimated Cost to Fix: Air struts: $800 - $1500+ per strut. Air compressor: $500 - $1000+. Valve block: $300 - $600+.
  • Recalls: None Found
• Control Arm Bushings Wear
  • Description/Symptoms: Clunking or rattling noises from the suspension, especially when going over bumps. Poor handling and uneven tire wear.
  • Solution: Replace worn control arm bushings. Often, it’s more cost-effective to replace the entire control arm assembly.
  • Estimated Cost to Fix: $300 - $800 per control arm.
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, inability to start the car, and potential loss of power to certain electrical components.
  • Solution: Replace the EIS module and potentially reprogram the key.
  • Estimated Cost to Fix: $800 - $1,500+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Issues
  • Description/Symptoms: Malfunctioning lights, wipers, or other electrical accessories. Can also cause issues with the car starting or running properly.
  • Solution: Diagnose and repair or replace the faulty SAM unit.
  • Estimated Cost to Fix: $500 - $1200+
  • Recalls: None Found

Exterior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, making unusual noises, or leaking water.
  • Solution: Repair or replace the sunroof motor, tracks, or seals.
  • Estimated Cost to Fix: $200 - $1000+ depending on the issue.
  • Recalls: None Found

Interior

• Command System Problems
  • Description/Symptoms: Malfunctioning screen, navigation issues, audio problems, or complete system failure.
  • Solution: Diagnose and repair or replace the COMAND unit.
  • Estimated Cost to Fix: $500 - $2000+ depending on the repair needed.
  • Recalls: None Found
• Seat Motor Issues
  • Description/Symptoms: Seats not adjusting properly, getting stuck in certain positions, or making grinding noises.
  • Solution: Replace the faulty seat motor or repair the seat mechanism.
  • Estimated Cost to Fix: $200-$800 per seat.
  • Recalls: None Found

Summary

The 2009 Mercedes-Benz CLK550, while a desirable vehicle, can present owners with a range of issues as it ages. Engine oil leaks and camshaft adjuster issues are common. The 7G-Tronic transmission can develop problems with the torque converter and valve body, leading to costly repairs. Suspension issues, especially with the Airmatic system (if equipped), can also be expensive to address. Electrical problems related to the EIS and SAM modules are also possible. While some of these issues may be minor, others can be significant and costly to repair, potentially making the overall ownership experience more expensive than anticipated.