Mercedes-Benz ML W164 Problems: If you go on a drive around your nearest town or city, you are going to be shocked by the number of enormous SUVs rolling around perfectly paved streets. Yep, the Mercedes-Benz ML W164 that we are going to be analyzing today is one of the first big luxury SUVs that are much more at home in cities and on the highways than off-road. SUVs like the W164 ML come packed with an insane amount of features, technology and engine power which makes them the perfect choice for highway cruising and showing off. Even after all these years, the W164 ML is looking good, really good for its age actually. But they are also commonly seen in service centers as all that technology and electronics start to break down as these cars age. Buying a W164 ML today takes some courage and patience, these are not cheap cars to own and never will be. And on that note, let’s see what are the most common Mercedes-Benz ML W164 Problems.
Major Mercedes-Benz ML W164 Problems
OM642 diesel engine problems on the W164 ML
All diesel variants of the W164 Mercedes ML feature the OM642 diesel engine which has a number of common problems such as oil cooler oil leaks, turbo inlet seal oil leaks, timing chain and tensioner problems, intake manifold problems and so on. To learn all about this engine and the problems you can expect, read our extensive guide to the OM642 diesel engine.
M272 and M273 petrol engine problems in the ML350 and ML500
These two petrol engines were fitted to other Mercedes models such as the W221 S Class and the C219 CLS Class. Both engines suffer from either balance shaft gear or idler gear problems. These problems were present up until 2008 when Mercedes-Benz sorted out this engine-threatening issue. Read more about the problem on our Mercedes CLS Problems article or by clicking here. These engines are also very sensitive to regular oil changes. Running these engines on worn-out oil can cause timing chain damage and other issues regarding the crankshaft and camshaft regulation.
ML W164 Airmatic problems
Most but not all Mercedes ML W164 came equipped with the Mercedes air suspension system called the Airmatic. Having four air springs, a compressor, an Airmatic control unit, valve block and distribution valves mean that many components can malfunction and you end up with very high repair bills. A single air spring can cost up to 1200$, without labor. To learn more about the Airmatic suspension read our Mercedes Airmatic Problems article.
Mercedes-Benz ML W164 7G-Tronic automatic transmission problems
The W164 Mercedes-Benz ML was one of the first Mercedes vehicles to feature the otherwise bulletproof 7G-Tronic automatic transmission. The early 7G automatic transmissions however were known for hard downshifting and overall bad quality of shifting. In certain cases, a simple transmission fluid replacement or software reprogramming can solve the issue. Generally speaking, the problem with these transmissions was faulty shift solenoids and connections to the shift solenoids on the conductor plate. Repairing conductor plates used to be impossible, but over the years a number of companies started offering repair services for the conductor plate and the transmission control module. Solenoids and various sensors (mostly speed sensors) can also be repaired. When taking into account the labor cost, this is still not a cheap repair.
M272 and M273 petrol engine intake manifold problems
The complex intake manifolds on the M272 and the M273 engines are very likely to cause problems sometimes in their lifespan. Tha all plastic manifolds have several issues, all of which we covered in the Mercedes CLS Problems article. Regular maintenance is the most important factor, so we advise you never to buy vehicles with poor maintenance history.
Transmission gear selector failure on the Mercedes ML W164
The W164 Mercedes ML features what we Europeans call an “American style” gear selector lever which is located on the right side of the steering wheel. This gear selector however is prone to common failures (not fun being stranded because you cant shift into Drive). A new one will cost you about 300$ new + the cost of labor for replacement.
Minor Mercedes-Benz ML W164 Problems
Mercedes-Benz ML W164 rusted brake lines
Many W164 ML owners are reporting braking problems due to rusted brake lines. Replacing the lines is a tedious job that must be executed with no errors. This problem is more common if you live in an area with a lot of snow and therefore salty roads. Have your brake lines regularly inspected to avoid problems while on the road.
Mercedes-Benz ML W164 4Matic problems
MLs with the “4Matic” all-wheel-drive system has problems that are mainly tied to high mileage damage. Seeing as many of these cars have a number of miles on them today, this is a real concern. The most common problem areas are the center differential bearing and rubber flex disc degradation. A failed center differential bearing will cause vibrations that you will feel emanating from the bottom of your car and noise, which all bad bearings are prone to making. A degraded flex disc will also cause metal clunking noises and excessive vibration.
Mercedes ML W164 steering wheel clunking
ML W164 owners are commonly reporting issues with noise coming from the steering column. The problem at fault is a worn-out upper steering shaft bearing that needs replacement.
Mercedes ML door mirrors not opening or closing fully
Side mirrors on the ML do open and close automatically (not on all MLs) but owners do have problems with this functionality. Most of the time the problem is just poor lubrication of the moving parts which makes them not open or close fully. In other cases, poor electrical connections might cause the problems as well.
Engine mount problems
Most of the engines fitted to the ML need to work harder to move the big SUV around, this makes them run a bit hotter than usual which causes greater damage to the engine mounts. Excessive vibration at startup is the most common symptom of failing engine mounts. Replace them as soon as possible to avoid further problems.
EGR valve problems
Clogged EGR valves on the diesel W164 ML make the car lose power or even leave you unable to drive. This is more common on vehicles that make a lot of short trips and city driving.
Body and interior W164 problems
Mercedes-Benz ML W164 rust problems
Older ML model years are prone to rust problems on the bottom of doors, wheel arches, and above the fuel tank. This is nothing but a consequence of poor metal protection from Mercedes. Vehicles that cover a lot of miles on salty roads develop rust problems much faster.
Knocking noise coming from the center console
The problem is rubbing the handbrake cable against the prop shaft. If the cable is rubbing, it needs to be replaced and refitted.
Electronic Mercedes-Benz ML W164 Problems
ML W164 Heated seat problems
Early 2006-2008 ML models are known for having problems with heated seats. The seat heater can short out and heat the seat indefinitely which warms up your behind for days. The opposite scenario is possible as well, the seat heater simply gives out or even releases a burning scent. Replacement is simple.
SAM module problems on the Mercedes ML W164
SAM modules or Signal Actuation Modules are nothing new, they have been in cars since the 90s. The SAM module controls things like lights, remote key functionalities, rear boot opening and so on. The SAM module on the W164 is fitted to the rear right corner of the ML and usually fails due to water intrusion. A poor right rear tail light seal allows the water to enter the vehicle and flood the SAM module.
W164 Suspension and brakes warning lights
When the front wheel speed sensor wires get damaged, the ML is likely to flash warning lights warning about suspension and brake issues. Replacing the before-mentioned wires solves the issue.
Mercedes ML steering wheel buttons problems
Certain owners are reporting complete failures of the steering wheel buttons. This usually happens as a consequence of an internal steering wheel short-circuit.
Interior cabin temperature problem
In some cases, the temperature of the interior may greatly vary compared to that set by the driver on the AC temperature dial. This happens due to a failed sun sensor, which calculates the amount of sunlight hitting the windshield. If the sensor fails or malfunctions, the AC system cannot regulate for the additional heat of the sun which is why the temperature of the air on the inside of the vehicle might not match the desired temperature.
Frequently asked questions
Are Mercedes-Benz W164 reliable?
These cars are 11 years old at the least, with that age, reliability is not something that can be guaranteed for these vehicles. There are many components that can fail which means you will spend more time at the service center than with newer vehicles. That being said, these vehicles, with proper maintenance can last a long time and cover 300,000 miles in their lifetime.
What is the meaning of ML in Mercedes-Benz?
Mercedes Benz ML is still an M Class vehicle and not an ML-Class vehicle. The L was added to prevent legal action from BMW’s M department. The L in ML stands for Luxury.
Conclusion and recommendation
We recommend that you choose late 2008, 2009, and 2010 model years of the ML. These model years have had all the problems which occurred at the beginning of the production sorted out which is a massive purchasing factor. Some of the major problems with the M272 and M273 engines were resolved in 2008 which makes later model years much more interesting and reliable.
With these vehicles, make sure you are not buying a car with little to no maintenance history. You will regret buying a poorly serviced ML with all your being and your wallet will suffer as well. Trust us, these cars are no joke, they are a big challenge to maintain. Good luck!