2012 Mercedes-Benz R350

The 2012 Mercedes-Benz R350 is a luxury minivan known for its spaciousness, comfortable ride, and upscale features. The R350 was available with either a 3.5L V6 gasoline engine or a 3.0L V6 diesel engine. The 3.5L gasoline engine produces 302 horsepower and 273 lb-ft of torque. Both engines were paired with a 7-speed automatic transmission. Owners often praise the R350 for its smooth ride, quiet cabin, and versatility, but some common complaints include electrical issues and high maintenance costs.

Engine

3.5L V6 Gasoline Engine

• Camshaft Adjuster Solenoid Failure
  • Description/Symptoms: Check engine light, rough idling, decreased fuel economy, and potential engine misfires.
  • Solution: Replace the faulty camshaft adjuster solenoid.
  • Estimated Cost to Fix: $200 - $500+
  • Recalls: None Found
• Oil Filter Housing Leak
  • Description/Symptoms: Oil leak near the top of the engine, low oil level, and potential engine damage.
  • Solution: Replace the oil filter housing and gasket.
  • Estimated Cost to Fix: $300 - $700+
  • Recalls: None Found

3.0L V6 Diesel Engine

• Diesel Particulate Filter (DPF) Issues
  • Description/Symptoms: Reduced engine performance, increased fuel consumption, and DPF warning light illuminated. Can also cause a CEL to illuminate.
  • Solution: Forced DPF regeneration, cleaning, or replacement.
  • Estimated Cost to Fix: $200 - $2000+
  • Recalls: None Found
• AdBlue (Diesel Exhaust Fluid) System Malfunctions
  • Description/Symptoms: Warning lights, reduced engine power, and potential inability to start the vehicle. Can also cause a CEL to illuminate.
  • Solution: Repair or replace faulty sensors, pumps, or injectors in the AdBlue system.
  • Estimated Cost to Fix: $300 - $1500+
  • Recalls: None Found

Transmission

7-Speed Automatic (7G-Tronic)

• Torque Converter Failure
  • Description/Symptoms: Shuddering during gear changes, especially at low speeds, and potential transmission slippage.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1500 - $3500+
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Harsh or delayed shifting, erratic gear selection, and transmission slippage.
  • Solution: Repair or replace the valve body.
  • Estimated Cost to Fix: $800 - $2500+
  • Recalls: None Found

Suspension

• Air Suspension Failure (if equipped)
  • Description/Symptoms: Vehicle sagging on one or more corners, ride height malfunction warning, and rough ride.
  • Solution: Replace faulty air struts, air compressor, or ride height sensors.
  • Estimated Cost to Fix: $800 - $3000+ per strut, $500 - $1500+ for the compressor
  • Recalls: None Found
• Airmatic Compressor Relay Failure (if equipped)
  • Description/Symptoms: Air suspension inoperable, vehicle sitting low, compressor not running. Can also cause the compressor to burn out.
  • Solution: Replace the relay for the Airmatic compressor.
  • Estimated Cost to Fix: $50 - $150
  • Recalls: None Found

Electrical

• Power Window Regulator Failure
  • Description/Symptoms: Window not operating, slow or erratic window movement, or clicking noise from the door.
  • Solution: Replace the faulty power window regulator.
  • Estimated Cost to Fix: $250 - $500+
  • Recalls: None Found
• Electronic Steering Lock (ESL) Failure
  • Description/Symptoms: Key cannot be turned in the ignition, steering wheel locked, and vehicle unable to start.
  • Solution: Replace or repair the ESL module.
  • Estimated Cost to Fix: $500 - $1500+
  • Recalls: None Found
• Glow Plug Module Failure (Diesel Only)
  • Description/Symptoms: Hard starting, especially in cold weather, check engine light, and potential rough idling.
  • Solution: Replace the glow plug module.
  • Estimated Cost to Fix: $300-$800+
  • Recalls: None Found

Exterior

• Sunroof Issues
  • Description/Symptoms: Sunroof does not open or close properly, gets stuck, or makes excessive noise when operating.
  • Solution: Repair or replace the sunroof motor, tracks, or other components.
  • Estimated Cost to Fix: $300 - $1000+
  • Recalls: None Found

Interior

• Navigation/Infotainment System Malfunctions
  • Description/Symptoms: Screen freezing, system reboots, inaccurate GPS, and audio issues.
  • Solution: Software update, component replacement.
  • Estimated Cost to Fix: $200 - $1000+
  • Recalls: None Found

Summary

The 2012 Mercedes-Benz R350, while offering a luxurious and spacious ride, can be prone to several issues. Engine problems, especially with the camshaft adjusters and oil filter housing on the gasoline engine, can lead to moderate repair costs. The diesel engine models can have issues with the DPF system. Transmission problems, particularly with the torque converter and valve body, can result in significant expenses. Air suspension issues, when equipped, are also costly to repair. Electrical problems, such as power window regulator and electronic steering lock failures, can add to the overall maintenance burden. The severity of these issues ranges from minor inconveniences to major repairs, with costs varying from a few hundred to several thousand dollars. Potential buyers should be aware of these common problems and factor in the possibility of higher maintenance costs when considering purchasing a 2012 R350.