2005 Mercedes-Benz CLK55 AMG

The 2005 Mercedes-Benz CLK55 AMG is a high-performance coupe featuring a hand-built 5.4L V8 engine producing 362 horsepower and 376 lb-ft of torque. This model came exclusively with a 5-speed automatic transmission. Owners often praise the car for its powerful engine, luxurious interior, and comfortable ride. Common complaints revolve around its relatively high running costs, particularly related to maintenance and fuel consumption, as well as some age-related reliability issues.

Engine

5.4L M113 V8

• Oil Leaks
  • Description/Symptoms: Oil leaks are common around the valve cover gaskets, oil filter housing gasket, and rear main seal. Symptoms include visible oil leaks, burning oil smell, and low oil level.
  • Solution: Replace the affected gaskets or seals.
  • Estimated Cost to Fix: $200 - $800+ depending on the location and severity of the leak.
  • Recalls: None Found
• Idler Pulley and Belt Tensioner Failure
  • Description/Symptoms: The idler pulley and belt tensioner can fail, leading to a squealing noise, belt slippage, and potential damage to other engine components.
  • Solution: Replace the idler pulley and belt tensioner.
  • Estimated Cost to Fix: $200 - $400
  • Recalls: None Found
• MAF (Mass Air Flow) Sensor Failure
  • Description/Symptoms: Rough idle, poor acceleration, decreased fuel economy, and potential check engine light.
  • Solution: Replace the MAF sensor.
  • Estimated Cost to Fix: $150 - $300
  • Recalls: None Found

Transmission

5-Speed Automatic (722.6)

• Transmission Conductor Plate Failure
  • Description/Symptoms: Harsh shifting, getting stuck in gear, or complete loss of gear engagement. This is a common issue on the 722.6 transmission.
  • Solution: Replace the conductor plate within the transmission. A transmission fluid and filter change is also recommended.
  • Estimated Cost to Fix: $800 - $1500
  • Recalls: None Found
• Slipping or Delayed Shifts
  • Description/Symptoms: Transmission slips between gears, delayed engagement, or erratic shifting behavior.
  • Solution: Perform a transmission service (fluid and filter change). If the problem persists, further diagnostics and possible valve body repair or replacement may be required.
  • Estimated Cost to Fix: $200 - $2000+ depending on the severity of the problem.
  • Recalls: None Found

Suspension

• Air Suspension Issues (If equipped)
  • Description/Symptoms: Sagging suspension, particularly overnight, noisy air compressor, and “Suspension Fault” warnings on the dashboard.
  • Solution: Diagnose and replace leaking air struts, air compressor, or air lines.
  • Estimated Cost to Fix: $500 - $2000+ per strut or compressor.
  • Recalls: None Found
• Control Arm Bushing Failure
  • Description/Symptoms: Clunking or rattling noises from the front or rear suspension, especially over bumps. Poor handling and uneven tire wear.
  • Solution: Replace the worn control arm bushings or the entire control arm.
  • Estimated Cost to Fix: $300 - $800+ per control arm.
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Difficulty starting the car, key not recognized, or complete failure to start.
  • Solution: Replace the EIS module and potentially reprogram the key.
  • Estimated Cost to Fix: $800 - $1500
  • Recalls: None Found
• Instrument Cluster Pixelation
  • Description/Symptoms: Pixels in the instrument cluster display fade or disappear, making it difficult to read information.
  • Solution: Repair or replace the instrument cluster.
  • Estimated Cost to Fix: $300 - $1000
  • Recalls: None Found

Exterior

• Rust
  • Description/Symptoms: Rust can appear on the wheel arches, door edges, and underbody, especially in regions with harsh winters or coastal climates.
  • Solution: Repair or replace rusted panels. Preventative rustproofing is recommended.
  • Estimated Cost to Fix: $500 - $5000+ depending on the extent of the rust.
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: Sunroof may be slow, noisy, or fail to open/close properly.
  • Solution: Clean and lubricate the sunroof tracks and mechanism. Repair or replace damaged components.
  • Estimated Cost to Fix: $200 - $800+
  • Recalls: None Found

Summary

The 2005 Mercedes-Benz CLK55 AMG, while a desirable performance car, does suffer from some common age-related issues. Engine oil leaks, transmission problems (specifically conductor plate failure), suspension issues (especially air suspension if equipped), and electrical problems (EIS failure and instrument cluster pixelation) are the most prevalent. Repair costs can range from a few hundred dollars for minor fixes to several thousand dollars for major component replacements. Prospective buyers should carefully inspect the vehicle and be prepared for potentially higher maintenance costs compared to more modern vehicles.