2014 Mercedes-Benz GL350
The 2014 Mercedes-Benz GL350 BlueTEC 4MATIC is a full-size luxury SUV known for its spaciousness, ride comfort, and fuel efficiency compared to its gasoline-powered counterparts. It features a 3.0-liter turbocharged diesel V6 engine producing 240 horsepower and 455 lb-ft of torque. Other engine options for the 2014 GL-Class include the GL450 with a 3.0L twin-turbo V6, the GL550 with a 4.7L twin-turbo V8, and the high-performance GL63 AMG with a 5.5L twin-turbo V8. All GL-Class models, including the GL350 BlueTEC, came standard with a 7-speed automatic transmission. Owners generally appreciate the GL350’s fuel economy, comfortable ride, and luxurious interior. Common complaints often revolve around the cost of maintenance and repairs, and potential issues with the diesel engine’s emissions system.
Engine
3.0L Turbocharged Diesel V6 (OM642)
- AdBlue Tank Heater Failure
- Description/Symptoms: The AdBlue tank heater can fail, causing a check engine light and potentially preventing the vehicle from starting in cold weather due to the DEF (Diesel Exhaust Fluid) freezing. Codes related to the heater circuit malfunction or DEF temperature sensor being out of range.
- Solution: Replace the AdBlue tank heater or the entire AdBlue tank assembly.
- Estimated Cost to Fix: $500 - $1500+
- Recalls: None Found
- Oil Cooler Seal Leaks
- Description/Symptoms: The oil cooler seals on the OM642 engine are prone to leaking, causing oil to drip onto other components and potentially leading to a burning smell.
- Solution: Replace the oil cooler seals. This often requires removing the intake manifold.
- Estimated Cost to Fix: $800 - $1800+
- Recalls: None Found
- Swirl Motor Failure
- Description/Symptoms: The swirl motor, responsible for controlling the intake manifold flaps for optimal combustion, can fail. This often results in a check engine light and reduced engine performance.
- Solution: Replace the swirl motor or repair the linkage.
- Estimated Cost to Fix: $500 - $1200+
- Recalls: None Found
- Diesel Particulate Filter (DPF) Issues
- Description/Symptoms: The DPF can become clogged, especially with frequent short trips. This leads to reduced engine performance, increased fuel consumption, and a check engine light.
- Solution: Perform a forced DPF regeneration, or replace the DPF if it is severely clogged.
- Estimated Cost to Fix: $300 - $800 (regeneration) / $1500 - $3000+ (replacement)
- Recalls: None Found
Transmission
7G-Tronic (722.9)
- Valve Body Issues
- Description/Symptoms: The 722.9 transmission valve body can experience wear and tear, leading to rough shifting, delayed engagement, or slipping between gears.
- Solution: Replace or rebuild the valve body.
- Estimated Cost to Fix: $800 - $2500+
- Recalls: None Found
- Torque Converter Failure
- Description/Symptoms: Torque converter can fail internally. Symptoms include shuddering at low speeds, especially during acceleration, unusual noises, and overall poor transmission performance.
- Solution: Replace the torque converter
- Estimated Cost to Fix: $1500 - $3500+
- Recalls: None Found
Suspension
- Air Suspension Leaks (Airmatic)
- Description/Symptoms: The Airmatic air suspension system can develop leaks in the air struts or air lines, causing the vehicle to sag, especially overnight. This can also lead to the air compressor working overtime and eventually failing.
- Solution: Replace the leaking air strut(s) or air lines. Replace the air compressor if it has been damaged due to overwork.
- Estimated Cost to Fix: $800 - $2000+ per strut, $500 - $1500+ for compressor replacement.
- Recalls: None Found
- Air Compressor Failure (Airmatic)
- Description/Symptoms: The air suspension compressor can fail completely or become weak, resulting in the vehicle failing to raise or maintain its ride height.
- Solution: Replace the air suspension compressor.
- Estimated Cost to Fix: $500 - $1500+
- Recalls: None Found
Electrical
- Battery Drain Issues
- Description/Symptoms: The GL350 can experience excessive battery drain, especially if the vehicle is not driven frequently. This can lead to a dead battery and difficulty starting the vehicle.
- Solution: Diagnose and repair the source of the battery drain, such as a faulty module or accessory that is not shutting off properly. Battery replacement may also be necessary.
- Estimated Cost to Fix: $100 - $500+ (diagnosis), $200 - $500+ (battery replacement), cost of repair varies based on the fault.
- Recalls: None Found
- Navigation/Infotainment System Issues
- Description/Symptoms: The navigation/infotainment system can experience glitches, freezing, or failure.
- Solution: Update the software, or replace the head unit.
- Estimated Cost to Fix: $100 - $300 (software update), $500 - $2000+ (replacement)
- Recalls: None Found
Exterior
- Tail Light Issues
- Description/Symptoms: The LED tail lights can have issues with the LEDs going out, causing a malfunction code.
- Solution: Replace the tail light assembly.
- Estimated Cost to Fix: $300-$800+
- Recalls: None Found
Interior
- Sunroof Issues
- Description/Symptoms: The sunroof mechanism can fail, causing the sunroof to become stuck, noisy, or inoperable.
- Solution: Repair or replace the sunroof mechanism.
- Estimated Cost to Fix: $500 - $1500+
- Recalls: None Found
Summary
The 2014 Mercedes-Benz GL350 BlueTEC 4MATIC offers a luxurious and comfortable ride, but potential buyers should be aware of common issues, particularly related to the diesel engine’s emissions system (AdBlue heater, DPF) and the air suspension. The 7-speed transmission and electrical systems can also present problems. While some repairs, like replacing oil cooler seals or swirl motors, are relatively moderate in cost, others, such as air suspension repairs or transmission valve body replacement, can be quite expensive. Addressing these issues proactively or having a pre-purchase inspection by a qualified mechanic familiar with Mercedes-Benz vehicles is highly recommended.