Mercedes SUV Problems: 6 Common Issues (Explained)

Mercedes-Benz has long offered drivers their own luxury take on the SUV, and the German manufacturer provides sleek design and top-tier performance.

Their models aren’t always completely fault-free, though – if you’re wondering whether they’re particularly prone to any mechanical issues, we’ve done some of the research for you.

Check out our list of the most common problems below.

1. Brake System Corrosion

One of the more wide-scale problems that Mercedes-Benz has dealt with is an issue with its braking system for some SUV models from 2006 through 2012.

The problem results from the fact that accumulated moisture may collect in the brake booster housing unit, causing corrosion and reducing the performance of the brake boosters.

If the corrosion is severe, drivers may need to apply much more pressure for the brakes to work, or the brakes may fail altogether.

The problem was discovered after a driver noticed and reported that they were having difficulty bringing their vehicle to a stop.

Mercedes conducted an investigation in 2021, which resulted in a recall for nearly 300,000 SUVs.

The affected models include GL-class, M-class, and R-class SUVs, and it was recommended that owners stop driving their vehicles until the inspection and necessary repairs could be done.

According to the brand, though, there have luckily been no injuries or crashes caused by the defect.

2. Faulty Third-Row Seats

A recent safety issue that cropped up on Mercedes-Benz GLS models has to do with the back row seats. Due to improper installation of the spring locks by the manufacturer, the third row seats don’t always stay locked in position.

While it may seem merely like an annoying defect, the malfunction could have serious consequences in the event of a crash – if the seats aren’t secure, those sitting in the back seat could sustain serious injuries.

To prevent this, Mercedes issued a recall on nearly 60,000 vehicles produced between 2018 and 2022.

Thankfully, there have been no reported injuries due to the problem, but if your vehicle is affected, it should be taken to a dealership for inspection and replacement free of charge as soon as possible.

You can also explore some problems with the Mercedes-Benz GLE.

3. Car Shutting Off When Driving

Some Mercedes drivers have reported that their cars have suddenly lost power while driving, leaving them to coast until they can pull over. Drivers of the ML350 and G500 models are particularly prone to this complaint.

The shut off would occur either on the road, or shortly after starting the car if the engine was hot. In some instances, the car would restart easily, but in others the engine would merely crank without starting.

For some drivers, the problem was accompanied by their check-engine light turning on, but other times the shut-offs would occur without warning.

Drivers have also reported rough engine sounds while idling would occur after restart.

A common reason for the problem has turned out to be a faulty camshaft adjuster solenoid; this part allows oil to flow through the variable valve timing system. 

Even if there are no drivability issues and the only sign of the problem is the check-engine light, a faulty camshaft can still lead to engine lubrication problems and even engine failure.

Replacing the part usually returns to timing of the engine to normal and resolves the issue. Some drivers, however, have had the same problem occur even with the replacement, indicating a larger problem with these Mercedes’s VVT systems.

Fixing the problem can run owners a bill of up to $5,000 if the vehicles doesn’t fall under warranty.

In other cases, the problem was due to a malfunctioning crankshaft position sensor, which monitors the rotation of the crankshaft in the engine.

This issue is less expensive to repair, usually running from $150 to $500.

You can read more here about general problems with Mercedes cars.

4. Loss of Power Steering

Another issue that many ML350 drivers had to deal with was a leaking steering rack.

The rack is responsible for communicating the turning of the steering wheel to the tires, and in cars with power steering systems, it relies on high-pressure fluids in order to move.

If the racks suffer leaks, the pressure of the fluid can no longer be maintained, leading to a failure of the power steering.

This not only makes handling the car difficult and unreliable, but can cause abnormal braking noises and eventually damage the power steering pump.

A new power steering rack can cost between $1,500 and $3,000, while a new pump is a bit less expensive, at around $800.

While Mercedes has issued a recall for the power steering hose clamp, the recall doesn’t seem to apply to all ML350 models that were affected.

The model years most affected by the leaks were from 2003 through 2005, and 2009 through 2013.

5. Rough Shifting and Transmission Problems

Some GL450 models have displayed problems with their 7-speed transmissions.

Many drivers report a jagged feeling when their vehicle goes up a gear, with the RPMs jumping before the car switches into a higher gear.

Some report that their cars have gotten stuck in a higher gear or in neutral. A restart often fixes the problem temporarily.

Mercedes has attributed the problem to an “internal component failure”, and released updated replacement parts for the vehicles experiencing the issue.

Though the rough shifting can be attributed to various mechanical problems, it seems that Mercedes’s 7-gear transmissions have some room for improvement.

The issue is most common for vehicles from between 2007 and 2014. You can also explore some problems with the Mercedes-Benz GLS.

6. Door Lock & Window Switch Failure

Many Mercedes SUVs have seen frequent issues in the past with the door lock and window switch systems.

For some drivers, particularly with ML350s from model years 2006 through 2008 and 2014, unlocking the car with the remote feature would result in the locks cycling rapidly from locked to unlock, making it difficult to open the doors. Some drivers experienced this problem as early as 10,000 miles.

For others, the window controls, door handles, and locks were all prone to premature failure, most often before the vehicle reached 100,000 miles.

This issue was most common on G500 models from 2002 through 2008.

While replacing the lock systems and window switches is a relatively inexpensive fix, the underlying issues with Mercedes’s electrical systems is still concerning.

For some drivers, the problem even persisted, with multiple replacements necessary in the span of a few years.

General Pros and Con for Mercedes SUVs

Pros

Even taking into account their mechanical irregularities, there are still many points where Mercedes-Benz SUVs shine:

• Near-unbeatable luxury interior
• Easy maneuverability & smooth ride
• Iconic design makes these cars a stylish status symbol
• Lots of cargo space, with a three-row option
• Offers the option of upscale off-roading – particularly the G-wagon

Cons

• Brake system corrosion
• Faulty third-row seats
• Loss of power steering
• Car shut off while driving
• Rough shifting
• Door switch failure

Please also check out our article about the best and worst years of the Mercedes-Benz GLK-Class, a small, luxurious crossover SUV.

What Do the Reviews Say?

Overall, reviewers agree that Mercedes-Benz delivers on the luxury pricetag of its SUVs, lauding the design and performance of the vehicles.

Car and Driver says of the 2023 GLS:

“Comfortable and surprisingly satisfying to drive, the GLS-class SUV earns the S in its name by doing a good impression of Benz’s ritzy S-class sedan,” while also applauding “the cabin’s contemporary tech and rich finishes, roomy interior, and refined powertrains.”

The GLS models are some of the most popular Mercedes models for leasing.

[Source: Car and Driver]

Where Mercedes can struggle, however, is in the brand’s tendency to offer more style than substance. Edmunds says of the latest G-wagon model:

“The G-Class relies on style and emotion, rather than planning or execution, to justify its price. There’s power and authority from behind the wheel, but this SUV is a mess when it comes to ergonomics and practicality. The technology is a letdown too.”

[Source: Edmunds.com]

Mercedes knows its audience, however, and many G-wagon drivers aren’t concerned with practicality – the car still has 4.9 out of 5 stars when it comes to owner reviews.

What’s the Resale Value On Mercedes SUVs?

Mercedes SUVs aren’t known for retaining their value, and can lose more than half of their value after five years as drivers flock to the newest model.

Mercedes-Benz GLE-Class Depreciation

Note: Estimates are based on resale of vehicle in good condition, with a original value of $90,322 in 2022.

Sources

– Mercedes Recalls SUVs to Fix Problem With Third-Row Seats – Consumer Reports

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ⓘ  The information in this article is based on data from National Highway Traffic Safety Administration (NHTSA) recall reports, consumer complaints submitted to the NHTSA, reliability ratings from J.D. Power, auto review and rating sites such as Edmunds, specialist forums, etc. We analyzed this data to provide insights into the best and worst years for these vehicle models.