2008 Mercedes-Benz GL450

The 2008 Mercedes-Benz GL450 is a full-size luxury SUV known for its spacious interior, comfortable ride, and powerful engine. The GL450 is powered by a 4.7L V8 engine producing 335 horsepower and 339 lb-ft of torque, paired with a 7-speed automatic transmission. Other engine options for the 2008 GL-Class include the GL320 CDI (3.0L diesel V6) and the GL550 (5.5L gasoline V8). Owners often praise the GL450 for its luxurious features, ample cargo space, and towing capability. Common complaints include higher than average maintenance costs, complex electronics, and occasional issues with the air suspension.

Engine

4.7L V8 (M273)

• Camshaft Adjuster Solenoid Failure
  • Description/Symptoms: Check engine light, rough idle, reduced engine power.
  • Solution: Replace faulty camshaft adjuster solenoid.
  • Estimated Cost to Fix: $300 - $600+
  • Recalls: None Found
• Valve Cover Gasket Leaks
  • Description/Symptoms: Oil leaks around the valve cover, burning smell, low oil level.
  • Solution: Replace valve cover gaskets.
  • Estimated Cost to Fix: $400 - $800+
  • Recalls: None Found

Transmission

7G-Tronic (722.9)

• Conductor Plate Failure
  • Description/Symptoms: Erratic shifting, transmission stuck in gear, limp mode.
  • Solution: Replace the conductor plate (valve body assembly).
  • Estimated Cost to Fix: $800 - $1500+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering or vibration at low speeds, stalling, transmission slipping.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1500 - $3000+
  • Recalls: None Found

Suspension

• Airmatic Suspension Compressor Failure
  • Description/Symptoms: Vehicle sagging, “Vehicle Too Low” warning message, air suspension not raising or lowering.
  • Solution: Replace the air suspension compressor.
  • Estimated Cost to Fix: $800 - $1500+
  • Recalls: None Found
• Airmatic Strut Failure
  • Description/Symptoms: Vehicle sagging on one corner, bouncy ride, hissing sound from strut.
  • Solution: Replace the faulty Airmatic strut.
  • Estimated Cost to Fix: $1000 - $2000+ per strut
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, unable to start the vehicle, steering wheel lock malfunction.
  • Solution: Replace the EIS module and program it to the vehicle.
  • Estimated Cost to Fix: $800 - $1800+
  • Recalls: None Found
• Fuel Pump Relay Failure
  • Description/Symptoms: Vehicle cranks but does not start, stalling.
  • Solution: Replace the fuel pump relay (often requires replacing the entire front SAM module).
  • Estimated Cost to Fix: $300 - $1000+
  • Recalls: None Found

Exterior

• Tail Light Assembly Cracking
  • Description/Symptoms: Visible cracks in the tail light lens, moisture inside the tail light.
  • Solution: Replace the tail light assembly.
  • Estimated Cost to Fix: $300 - $600+ per light
  • Recalls: None Found

Interior

• Sunroof Malfunction
  • Description/Symptoms: Sunroof not opening or closing properly, getting stuck, making unusual noises.
  • Solution: Repair or replace sunroof motor, cables, or other components.
  • Estimated Cost to Fix: $400 - $1200+
  • Recalls: None Found

Summary

The 2008 Mercedes-Benz GL450, while a luxurious and capable SUV, can present owners with a variety of potential issues. The most significant concerns often revolve around the Airmatic suspension, transmission, and electrical systems. Repairs can be costly, especially for the suspension and transmission components. Owners should be aware of these potential problems and factor them into their ownership budget.