2007 Mercedes-Benz ML320

The 2007 Mercedes-Benz ML320 is a mid-size luxury SUV that blends comfort, capability, and style. The ML320 came equipped with a 3.0L V6 diesel engine, producing 215 horsepower and 398 lb-ft of torque. Other engine options for the 2007 M-Class include a 3.5L V6 gasoline engine (ML350) and a 5.0L V8 gasoline engine (ML500). All engines were paired with a 7-speed automatic transmission (7G-TRONIC). Owners often praised the ML320’s comfortable ride, luxurious interior, and robust build quality. Common complaints revolved around higher maintenance costs, electrical gremlins, and occasional issues with the diesel engine’s emissions system.

Engine

3.0L V6 Diesel (OM642)

• Oil Cooler Seal Leak
  • Description/Symptoms: Oil leak, often dripping onto the serpentine belt causing it to shred. Oil may also leak down the back of the engine.
  • Solution: Replace the oil cooler seals.
  • Estimated Cost to Fix: $500 - $1200+
  • Recalls: None Found
• Swirl Motor Failure
  • Description/Symptoms: Check Engine Light with codes related to the intake manifold swirl flaps. Reduced engine performance.
  • Solution: Replace the swirl motor or intake manifold assembly (depending on the severity). A software update may also be needed in some cases.
  • Estimated Cost to Fix: $500 - $1500+
  • Recalls: None Found
• EGR Valve Issues
  • Description/Symptoms: Rough idling, stalling, Check Engine Light, excessive smoke from the exhaust.
  • Solution: Clean or replace the EGR valve.
  • Estimated Cost to Fix: $200 - $800+
  • Recalls: None Found

Transmission

7G-TRONIC (722.9)

• Valve Body Issues
  • Description/Symptoms: Harsh shifting, slipping between gears, failure to shift, or getting stuck in a gear.
  • Solution: Replace or rebuild the valve body. In some cases, a transmission flush and software update may resolve the issue, but valve body replacement is often necessary.
  • Estimated Cost to Fix: $800 - $2500+
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering at low speeds, especially when accelerating, transmission slipping, and potential stalling.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1500 - $3500+
  • Recalls: None Found

Suspension

• Airmatic Suspension Failure (if equipped)
  • Description/Symptoms: Vehicle sagging on one or more corners, failure to raise or lower, “Visit Workshop” message on the dashboard. Noises coming from the air compressor.
  • Solution: Diagnose and replace faulty components, such as air struts, air compressor, or valve block.
  • Estimated Cost to Fix: $800 - $3000+ (per strut)
  • Recalls: None Found
• Ball Joint Wear
  • Description/Symptoms: Clunking noises from the front suspension, especially when going over bumps. Poor handling.
  • Solution: Replace worn ball joints.
  • Estimated Cost to Fix: $300 - $800+ per side
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, difficulty starting the vehicle, or complete failure to start.
  • Solution: Replace the EIS module and reprogram it to the vehicle.
  • Estimated Cost to Fix: $800 - $1800+
  • Recalls: None Found
• SAM (Signal Acquisition Module) Issues
  • Description/Symptoms: Various electrical malfunctions, such as lights not working, wipers malfunctioning, or issues with the central locking system.
  • Solution: Diagnose and replace the faulty SAM unit. Reprogramming may be required.
  • Estimated Cost to Fix: $500 - $1500+
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Battery constantly draining, requiring frequent jump starts.
  • Solution: Diagnose and repair the parasitic draw. This can be time-consuming and may involve multiple components.
  • Estimated Cost to Fix: $200 - $1000+ (depending on the source of the drain)
  • Recalls: None Found

Exterior

• Rust Issues (Especially in areas with road salt)
  • Description/Symptoms: Rust forming on the lower body panels, wheel arches, and around the door edges.
  • Solution: Repair or replace rusted panels.
  • Estimated Cost to Fix: $500 - $3000+ (depending on the severity)
  • Recalls: None Found

Interior

• Sunroof Issues
  • Description/Symptoms: Sunroof not opening or closing properly, getting stuck, or making unusual noises.
  • Solution: Repair or replace the sunroof motor, tracks, or related components.
  • Estimated Cost to Fix: $300 - $1200+
  • Recalls: None Found
• Command System Failure
  • Description/Symptoms: Navigation, radio, or display screen malfunctioning or failing to power on.
  • Solution: Diagnose and repair or replace the COMAND unit.
  • Estimated Cost to Fix: $500 - $2000+
  • Recalls: None Found

Summary

The 2007 Mercedes-Benz ML320 offers a comfortable and luxurious driving experience, but potential buyers should be aware of the common issues. The diesel engine can experience problems with oil leaks, swirl motors, and EGR valves. The 7G-TRONIC transmission is prone to valve body and torque converter failures. The Airmatic suspension (if equipped) can be costly to maintain, and electrical issues with the EIS and SAM modules are common. Rust can also be a concern, especially in colder climates. Overall, these issues can range from moderately expensive to significantly expensive, making a thorough pre-purchase inspection crucial.