2008 Mercedes-Benz GL320

The 2008 Mercedes-Benz GL320 Bluetec is a full-size luxury SUV known for its spacious interior, comfortable ride, and towing capability. The GL320 Bluetec features a 3.0L turbodiesel V6 engine producing 215 horsepower and 398 lb-ft of torque. Other engine options for the 2008 GL-Class include a 4.6L V8 (GL450) and a 5.5L V8 (GL550). All engine options are paired with a 7-speed automatic transmission. Owners often praise the GL320 for its fuel economy compared to other SUVs in its class, its luxurious features, and its ability to comfortably transport up to seven passengers. Some common complaints include the high cost of maintenance and repairs, particularly concerning the diesel engine and its emissions control system.

Engine

3.0L Turbodiesel V6 (OM642)

• Oil Cooler Seal Leaks
  • Description/Symptoms: Oil leak originating from the oil cooler located in the V of the engine. This can lead to a noticeable oil smell, oil spots under the vehicle, and low oil levels.
  • Solution: Replacement of the oil cooler seals.
  • Estimated Cost to Fix: $800 - $1500+
• Swirl Flap Motor Failure
  • Description/Symptoms: Check Engine Light, reduced engine power, and potentially limp mode. Can be diagnosed by codes P2004, P2005, P2006.
  • Solution: Replacement of the swirl flap motor or intake manifold.
  • Estimated Cost to Fix: $500 - $1200+
• Diesel Particulate Filter (DPF) Clogging
  • Description/Symptoms: Reduced engine performance, increased fuel consumption, and a Check Engine Light.
  • Solution: DPF regeneration (if possible), or replacement of the DPF.
  • Estimated Cost to Fix: $300 - $2000+
• Glow Plug Failure
  • Description/Symptoms: Difficult starting, especially in cold weather, Check Engine Light.
  • Solution: Replacement of faulty glow plugs.
  • Estimated Cost to Fix: $200 - $500+
• Turbocharger Issues
  • Description/Symptoms: Lack of power, whistling noise from the engine, Check Engine Light.
  • Solution: Diagnose the issue with the turbocharger, which can range from boost leaks to complete turbo failure. Repair or replacement of the turbocharger.
  • Estimated Cost to Fix: $1500 - $3500+

Transmission

7-Speed Automatic (722.9)

• Valve Body Issues
  • Description/Symptoms: Harsh or delayed shifting, slipping between gears, transmission getting stuck in one gear.
  • Solution: Replacement or rebuild of the valve body.
  • Estimated Cost to Fix: $1200 - $2500+
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, stalling, or complete loss of drive.
  • Solution: Replacement of the torque converter.
  • Estimated Cost to Fix: $1000 - $2000+
• Conductor Plate Failure
  • Description/Symptoms: Transmission stuck in limp mode, inability to shift gears, error codes related to speed sensors.
  • Solution: Replacement of the conductor plate, often requires valve body removal.
  • Estimated Cost to Fix: $800 - $1500+

Suspension

• Airmatic Suspension Failure
  • Description/Symptoms: Vehicle sagging on one or more corners, failure to raise or lower, error messages on the instrument cluster.
  • Solution: Diagnose and replace faulty components such as air struts, air compressor, or valve block.
  • Estimated Cost to Fix: $800 - $2000+ per strut, $500 - $1200+ for compressor.
• Air Compressor Failure
  • Description/Symptoms: The suspension no longer raises or lowers the vehicle.
  • Solution: Replacement of the air compressor.
  • Estimated Cost to Fix: $500 - $1200+
• Air Spring Leaks
  • Description/Symptoms: The suspension no longer raises or lowers the vehicle.
  • Solution: Replacement of the air springs.
  • Estimated Cost to Fix: $800 - $2000+ per spring

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, inability to start the vehicle, steering wheel lock malfunction.
  • Solution: Replacement of the EIS.
  • Estimated Cost to Fix: $800 - $1500+
• Battery Drain Issues
  • Description/Symptoms: Car battery draining overnight or within a few days, requiring frequent jump starts.
  • Solution: Diagnose and address the parasitic drain caused by a faulty module or component.
  • Estimated Cost to Fix: $200 - $1000+ (depending on the source of the drain).
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Issues with various electrical functions such as lights, wipers, door locks, or power windows.
  • Solution: Replacement of the faulty SAM unit.
  • Estimated Cost to Fix: $500 - $1200+
• Glow Plug Relay Failure
  • Description/Symptoms: Difficult starting, especially in cold weather, Check Engine Light.
  • Solution: Replacement of faulty glow plug relay.
  • Estimated Cost to Fix: $150 - $300+

Exterior

• Tail Light Assembly Issues
  • Description/Symptoms: Malfunctioning or dimming tail lights, brake lights, or turn signals due to faulty wiring or bulb sockets.
  • Solution: Replacement of the tail light assembly or repair of the wiring harness.
  • Estimated Cost to Fix: $200 - $500+ per assembly

Interior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, getting stuck, or making unusual noises.
  • Solution: Diagnose and repair or replace faulty sunroof components such as the motor, tracks, or seals.
  • Estimated Cost to Fix: $300 - $1000+

Recalls:

• 2012120003
• 2013070004
• 2013070003
• 2013080005
• 2016070003
• 2016070002
• 2017020004
• 2017020003
• 2020020008

Summary

The 2008 Mercedes-Benz GL320 Bluetec can be a luxurious and capable SUV, but potential buyers should be aware of the common issues that can arise, particularly with the diesel engine, air suspension, and electrical systems. Repair costs can be significant, especially for the air suspension and engine-related issues. Addressing these issues can range from a few hundred dollars for simple fixes to several thousand dollars for more complex repairs like turbocharger or valve body replacements.