The Mercedes ML320 was in production between 1998 and 2009 and in this time the ML spawned two different generations. The W163 was in production between 1998 and 2005 while the W164 was in production between 2005 and 2009.
The first generation of the ML is now a relatively old car and it tends to experience quite a bit of issues such as engine issues, steering system issues, and service brakes issues. The second generation of the ML is a lot more reliable than the first, and the problems typically list electrical issues, engine issues, and steering system issues.
Both of these ML320 generations are not the most reliable Mercedes SUVs ever and they tend to cost quite a bit of money to maintain. All in all, they are still comfortable and luxurious feeling to drive, but if you want a more up-to-date Mercedes mid-size SUV, you should look for the 3rd generation ML.
Most issues that tend to plague these early ML models are due to lackluster maintenance. However, some of them are more serious than others. You should look for well-kept relatively low-mileage examples of each if you want a relatively manageable ownership experience.
Mercedes ML320 W163 engine and engine cooling issues
The first generation of the ML320 is known to experience trouble with the harmonic balance pulley, the catalytic converters, manifold/header issues, and EGR value-associated issues. All of these are costly to repair while some of them sometimes appear on both low mileage and high mileage examples.
If you sense your ML320 engine is idling rough, it is a bit too noisy, has trouble starting, or dies on you without any obvious cause, you should take it for a diagnosis immediately as some of these are known to cause many issues down the line.
Mercedes ML320 W163 steering system issues
The W163 ML320 is known to experience power steering wheel-related issues relatively often. Many owners complained about power steering hose breaking, power steering fluid leaks, connection issues, and issues with the hydraulic power steering system as a whole.
Some of these tend to appear while driving which means that it is never a good thing to lose power steering while traveling on a highway. You need to keep an eye on these at all times if you want a safe and manageable driving experience. Also, be sure to keep an eye out for inconsistent steering assistance as this can more issues later on.
Mercedes ML320 W163 service brakes issues
Many first-gen ML320 owners reported relatively issues with the brake system where the car abruptly comes to a halt after the ESP light turns on the dashboard. It seems like this issue happens because the steering yaw rate sensor starts misreading and the car thinks that something is wrong and thus it independently stops the car.
This can be a huge issue while driving, so be sure to check these sensors and systems out of you are looking to buy a W163 ML320.
Mercedes ML320 W164 electrical issues
The second generation of the ML320 is indeed a lot more reliable than the first, but even these are known to experience all sorts of electrical issues. Several owners have reported that many in-car electronics fail from time to time. These include power tailgate issues, exterior lightning issues, and interior switches.
Many owners reported that most of these are being caused due to water ingress in several different areas of the car. Some owners reported that this is mostly down to low-quality water seals for the hood, the sunroof, the trunk, and the door jam areas.
Mercedes ML320 W164 engine and engine cooling issues
The ML320 uses a reliable and fairly dependable engine. However, many owners still reported that the car tends to stall, especially if the camshaft sensor dies. Engine leaks are also a common theme for older European luxury cars while increased oil consumption is also prevalent with higher mileage examples.
Leaks such as these can sometimes result in a fire and there are quite a few instances where people lost their ML320s due to fire-related damages.
Mercedes ML320 W164 steering system issues
The steering system is a well-known weak point of the ML320 and there are lots of data online that tends to discuss these issues more thoroughly. Power steering system issues include power steering fluid leaks, lack of power steering, growling noises, front bearing issues, and many piping and connection issues.
These can also be relatively dangerous, so be sure to keep an eye out on these if you are interested in buying a Mercedes ML320.
Years with a lot of problems
1998 Mercedes-Benz ML320 Problems
- Drive Authorization’s Inability to Recognize Keys Causes “No Start”
- Brake light switch failure may cause ESP/BAS warning lights
- Electric switches in door latches may fail
- Power Window Main Switch may fail
- Crankshaft Position Sensor Failure Causes Engine Performance Problems
1999 Mercedes-Benz ML320 Problems
- Drive Authorization’s Inability to Recongnize Keys Causes “No Start”
- Brake light switch failure may cause ESP/BAS warning lights
- Electric switches in door latches may fail
- Power Window Main Switch may fail
- Crankshaft Position Sensor Failure Causes Engine Performance Problems
- Doors Storage Pockets may become unglued and fall
2000 Mercedes-Benz ML320 Problems
- Drive Authorization’s Inability to Recongnize Keys Causes “No Start”
- Brake light switch failure may cause ESP/BAS warning lights
- Electric switches in door latches may fail
- Power Window Main Switch may fail
- Crankshaft Position Sensor Failure Causes Engine Performance Problems
- Doors Storage Pockets may become unglued and fall
FAQ Section
Is the Mercedes W164 ML320 more reliable than the W163 ML320?
The second generation of the ML320 is a lot more reliable than the first generation. That is because the 1st gen ML is now more than 20 years old while also being a tremendously complex car to begin with. This means that cars such as these tend to have lots of issues as time goes on, especially if they are not maintained correctly.
Even so, that does not really mean that the W164 ML320 is any more reliable because it isn’t. If you want these cars, be sure to find one that is 1in adequate condition, even if it means cashing out a few extra grand.
Which engine is in the Mercedes ML320?
The first generation ML320 uses a 3.2L V6 with 218hp and 228lb-ft of torque while the W164 generation also uses a 3.0L V6 with 220hp and 398lbft of torque. The second-generation ML320 is a lot more desirable because it is a lot newer.
It’s safe to say both of these powerplants are more than enough for 99%, but the W164 engine offers more torque which makes it more effortless and fitting for a large SUV.
Should I buy the Mercedes ML320?
You should skip buying the first generation of the ML because it is not the most reliable, nor the most modern car out there. The second generation of the ML320 is a lot better, but it is still not on par with modern-day cars.
If you are buying one of these as your daily driver, be sure to buy one with not too many miles on the clock. Also be sure to check all of the vulnerable areas, especially the steering system and the engine-related issues.
