2003 Mercedes-Benz CL55 AMG

The 2003 Mercedes-Benz CL55 AMG is a performance coupe boasting a supercharged 5.4L V8 engine producing 493 horsepower and 516 lb-ft of torque. The other engine options for the CL-Class of this era were the naturally aspirated 5.0L V8 in the CL500 and the V12 in the CL600 and CL65 AMG. The CL55 AMG is generally praised for its powerful engine, luxurious interior, and comfortable ride but can be criticized for its complex and potentially expensive maintenance. Common complaints include the air suspension system’s reliability and the potential for costly repairs. It is exclusively paired with a 5-speed automatic transmission.

Engine

5.4L Supercharged V8 (M113K)

• Supercharger Clutch Failure
  • Description/Symptoms: A whining or grinding noise from the supercharger, particularly at lower RPMs. Loss of boost and reduced acceleration.
  • Solution: Replace the supercharger clutch.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Crankshaft Position Sensor Failure
  • Description/Symptoms: Intermittent stalling, difficulty starting, and a check engine light.
  • Solution: Replace the crankshaft position sensor.
  • Estimated Cost to Fix: $200 - $400
  • Recalls: None Found
• Fuel Injector Issues
  • Description/Symptoms: Rough idling, misfires, and decreased fuel economy.
  • Solution: Diagnose the faulty injector(s) and replace as needed.
  • Estimated Cost to Fix: $200 - $500+ (depending on number of injectors)
  • Recalls: None Found

Transmission

5-Speed Automatic (722.6)

• Transmission Conductor Plate Failure
  • Description/Symptoms: Harsh or delayed shifting, getting stuck in a gear, and a “limp home” mode.
  • Solution: Replace the transmission conductor plate and filter and flush the transmission fluid.
  • Estimated Cost to Fix: $800 - $1,500
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Slipping between gears, erratic shifting, and general transmission malfunction.
  • Solution: Rebuild or replace the valve body.
  • Estimated Cost to Fix: $1,200 - $2,500+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, stalling when coming to a stop, and poor acceleration.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1,000 - $2,000+
  • Recalls: None Found

Suspension

• ABC (Active Body Control) Suspension Leaks
  • Description/Symptoms: Car leaning to one side, suspension sagging overnight, warning messages on the dash. Fluid leaks near struts, pump, or valve blocks.
  • Solution: Identify and repair leaks, which may involve replacing struts, hoses, the pump, or valve blocks. A complete system flush is often recommended.
  • Estimated Cost to Fix: $500 - $3,000+ per component depending on what needs to be replaced.
  • Recalls: None Found
• ABC Pump Failure
  • Description/Symptoms: Loud whining noise from the pump, stiff suspension, and warning lights on the dash. Complete suspension failure is possible.
  • Solution: Replace the ABC pump.
  • Estimated Cost to Fix: $1,200 - $2,500+
  • Recalls: None Found
• ABC Strut Failure
  • Description/Symptoms: Leaks, sagging, and uneven ride height.
  • Solution: Replace the strut.
  • Estimated Cost to Fix: $1,000 - $2,000+ per strut
  • Recalls: None Found

Electrical

• Instrument Cluster Pixelation
  • Description/Symptoms: Pixels missing from the LCD screens in the instrument cluster, making it difficult to read information.
  • Solution: Repair or replace the instrument cluster.
  • Estimated Cost to Fix: $300 - $1,000+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Various electrical malfunctions, such as malfunctioning lights, wipers, or door locks.
  • Solution: Diagnose and replace the faulty SAM unit.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found
• Seat Control Module Failure
  • Description/Symptoms: The seats are inoperable or move erratically.
  • Solution: Replace the seat control module
  • Estimated Cost to Fix: $400 - $800+
  • Recalls: None Found

Exterior

• Sunroof Malfunction
  • Description/Symptoms: Sunroof failing to open or close properly, getting stuck, or making grinding noises.
  • Solution: Repair or replace the sunroof motor, regulator, or cables.
  • Estimated Cost to Fix: $300 - $1,000+
  • Recalls: None Found

Interior

• Headliner Sagging
  • Description/Symptoms: The headliner fabric detaches from the roof and sags down.
  • Solution: Replace or re-glue the headliner fabric.
  • Estimated Cost to Fix: $300 - $800
  • Recalls: None Found

Summary

The 2003 Mercedes-Benz CL55 AMG offers exhilarating performance but is prone to some potentially costly issues. The air suspension and transmission, in particular, can be expensive to repair. Electrical gremlins are also common. Prospective buyers should be aware of these potential problems and budget accordingly for maintenance and repairs. The severity of issues can range from minor electrical malfunctions to complete suspension or transmission failure. Costs can vary widely depending on the specific issue and the repair shop but can easily reach thousands of dollars.