Common Mercedes Problems

Without going into too much technical detail these bushings are small rubber components found in the front suspension. They are fluid filled and have a tendency to crack open when old. Not only is this bad because the suspension won’t be functioning properly, but it can also make a bit of a mess. A bumpy ride and odd tyre wear can be an indicator that these need looking at. As well as these parts Mercedes also seem prone to ball joint wear, sway bar links and more. If you are looking at a car near the 100,000 mile mark be aware of all of these, though some reports suggest anything over 60,000 miles could be prone to problems.

Yes, the mighty Merc has been known to be susceptible to rush. While this is certainly not all Mercedes models it affects enough of the older ones to make it worth mentioning. Mainly from the 90s and early 00s many of the models were prone to rust in high wear areas. There are a few theories about this but generally its accepted that the cost of making the cars was getting too high. So, in order to remain competitive Mercedes sourced cheaper steel and used less paint. This leads to thinning in certain areas and rust taking hold. If you are looking at an older Mercedes then have a really good look around door sills, wheel arches and underneath the footwells among other spots. If the rot has set in, then walk away because it could get very costly!

In older models Mercedes used solid rubber for engine mounts. These were designed to reduce vibration coming from the engine and being transmitted through the car to the occupants. They worked well, however, as they age these mounts can perish and split. You should be able to feel if these mounts have gone as there will be noticeable vibration as well as a possibly clunk under acceleration. Later models used oil filled mounts which, again, worked really well but these too have a habit of giving up after about 100,000 miles and leaking fluid. The symptoms are the same and mounts are not very expensive to get changed. The problem is, if you notice vibrations and clunking in a car you are buying you have to be pretty sure you know it’s the mounts or it could be something really serious

It is important to state it is not an exclusively Mercedes problem, but Merc window regulators do have a habit of failing. It is something both BMW and Audi suffer from among other brands. There are a number of parts to a window regulator but often if it’s the pulleys that wear and become detached. Check for slow or non-opening windows when you view a car.

Post-2000 Mercedes starting using air suspension in some models and this was later rolled out to a lot more. While the system certainly gives a very high-quality ride it isn’t without its problems. Issues can occur with the air suspension bags and the relays too. The struts can fail totally leaving one corner of the car much lower than the rest. Naturally, this means it is very safe to drive and would need to be repaired right away. Leaking air struts can be hard to notice if it’s a very small leak. Over a long period, a small leak can even cause problems with the compressor itself.

While not a big common problem there are reports of “cats” failing on Mercedes cars at mileages of 60,000 which is quite low. Replacing a catalytic converter is expensive so it really isn’t something you want happening. Signs of an issue include misfiring, sluggish acceleration and general performance problems.

The Mercedes auto gearbox is actually rather brilliant but… the 13-pin connector and the valve body are not so good and certainly the weak link. These can fail and cause shifting issues like not going into gear. They are not a huge problem to get fixed which is good news. Make sure you check the shift from park to drive a few times when viewing a car to make sure it works as it should.

This one is a little technical but there are some common starting problems with Mercedes engines. It is all down to a sensor in the engine that measures if the engine is in the top dead centre position (TDC). Because this fails the engine thinks it’s not aligned and simply wont turnover. There is some evidence that you do get some warning of this with odd times when it wont start and gradually these times get more frequent. As always, try and view a car with a cold engine and see how it starts but this could be a hard one to spot on a viewing.

Mercedes make great engines, there is no doubt about that, and firing problems are quite common when an engine gets past the 100,000 mark. Things like coils and spark plugs need replacing as general wear and tear items but many Merc engines seem to need this kind of work at far lower mileages. Misfires and failing spark plugs have been seen in 60,000-mile cars which is not really what you would expect from Mercedes Benz.

It is fair to say Mercedes Benz are at the cutting edge of car engineering and this can be a good and bad thing. One of the reasons they have a list of common faults is that they are always adding in new tech that can sometimes not age too well. You could argue that as a luxury brand a Mercedes is designed to be a car people buy new. Once it gets past 100,000 miles and becomes affordable for everyone much of the cutting-edge tech has got a little old and worn. Many of the systems are very complex, for good reason at the point of design, but often cause issues in the real world. The driving experience is amazing and much of this is down to complex mechanicals and impressive technology. But as well as ageing this stuff is complicated and expensive to fix when it does fail.

It is really important to be aware that while Mercedes do make brilliant cars that are pretty reliable, they also come with a hefty price tag for servicing, repairs and general maintenance. Make sure you use our car check to see how the used Merc you are looking at has been treated, has it been serviced, what MOT history has it had and more!