Buying a used Mercedes S-class (W221) – 2006-2013, Ultimate Buying Guide with Common Issues

OK, comrades lets get into this Just look at this Mercedes S class W221 We should all agree that the exterior of this vehicle still looks pretty awesome, and expensive, even though nowadays almost anybody can buy this thing In fact, this particular S class which you are looking at is for sale for 6 950 € only However keep in mind that the maintenance and repair costs of this Mercedes, can be pretty easily the same as the buying price As they say, if you can’t stand the heat stay out of the kitchen! The very clean and simple layout of the interior still looks nice and not very dated, even though it was made in a time when the phones were just phones But even though it was made 15 years ago I can still talk about the various bourgeoisie features for hours, however there is no time for this so I will just briefly mention a couple of things like the: very comfortable front power seats with an optional massage function, the night vision which is still impressive, the split view multimedia system screen which can show 2 different things at the same time at 2 different angles is interesting, the ambient lightning all over the dash and door panels is nowadays nothing unusual, the noise insulating infrared-reflecting double glazing is cool, the various safety features can be useful, the automatic AC with countless settings- with slightly adjustable footwell temperature is maybe not that necessary, and I could continue, forever Of course the rear passengers can have almost every comfort feature in the back as well but that should be obvious The build quality is overall very good, and the used materials are mostly durable But nothing is perfect so there are a couple of maybe surprising flaws, like the: -soft touch coating of the buttons on the steering wheel on the before facelift cars This coating becomes worn and sticky and it will look horrible Then there are many cases of more or less loose leather on the front armrest, but occasionally also on the door panel armrest + on the before facelift cars the front driver’s seat base leather can have the same cosmetical issue But for more information about the interior visit my website Luckily unlike the predecessor, this S class is not famous for rust issues And it seems like Mercedes wanted to be really sure that it won’t rust that much, so the hood, front fenders, doors and the trunk lid are made from aluminum And of course the rust protection of the remaining parts is also very good To top of that according to the original brochure: the clearcoat of this Mercedes is more resistant than the conventional clearcoats, by virtue of it’s particularly dense molecular structure whatever those last words supposed to mean So basically the paintjob of your S class should remain nice and shiny for a long time, and it’s a bit more resistant to scratches, weathering, temperature fluctuations and even chemical attacks! But let’s move onto the more common possible issues: -I will start with the front optional dynamic multicontour seats which looks simple, and yet they are actually complex They contain numerous air bladders, valves and hoses for the air bladders, electronic control modules, motors for seat adjusting, fans for the seat ventilation and the seat heating pads To top of that there is also a separate external air pump for the bladders located in the trunk And what can go wrong? Well, mostly the air bladders can leak somewhere, then occasionally the electronic modules can be faulty or they will only need a software update, and sometimes even the seat wiring can be damaged All in all, it’s really important to check all the adjustments of these seats The regular adjustments are controlled by the seat buttons on the door, and all the other adjustments with the massage feature are accessible on the center screen after you press the button on the center console -Then check the radio and the sound from the multimedia system, since there are cases of dead amplifiers -After this there is the AC system which can have a couple of issues as well First of all the blower motor itself can often fail completely, or it will just occasionally cut off If it dies then first you can try to clean it with compressed air, which will bring it back from the dead if you are lucky, if not then just buy a new one Also keep in mind, that sometimes not the motor but the blower regulator can fail which is next to the motor And by the way, if your car is equipped with the 4 zone AC then the rear blower motor regulator

can fail too causing the same issue as the front After you checked the damn blower motor, you should also check all the temperature settings Since the front change-over-valve which is located under the windshield wipers can fail, causing only cold air to blow from the front vents This is pretty inconvenient in winter but the new valve is cheap and replacing it is also not rocket science But this is not the only valve which can fail, because if you have 4 zone AC, then the valve which controls the rear AC temperature can fail too However in this case the situation will be the exact opposite of the front valve failure The faulty AC valves for the rear AC are located behind the passenger/right front wheel well liner so again, replacing this part is not hard but in this case the valve is more expensive -Then there are more often cases of leaking windshield washer fluid + don’t forget to test the windshield washer, because the washer motors mounted on the tank can break -Next, keep in mind that this Mercedes can be equipped with the regular or with the panoramic sunroof Either way try to open and close it a couple of times, since the sunroof can get stuck because of the skipping motor which will in this case gets loose and make a loud clicking/rattling skipping noise The regular sunroof has only 1 motor, but the panoramic sunroof has 3 of these motors, since in this case the sunshades are also electronically operated and guess what! The sunshade motors can skip as well But luckily if the gear on the motor is not worn then you can fix this issue pretty easily for free For more information visit my website These are more or less the main possible issues However you have to keep in mind that because of the bigger amount of electronics, there is a higher chance of various electronic failures, although mainly just on the before facelift cars Either way, to minimize the electronic issues you really should have the battery and the alternator in a very good condition! -The alternator is not famous for premature failure, although it can be of course worn because of the bigger load it has to bear On the other side there are more cases of faulty voltage regulator behind the alternator which will cause voltage fluctuation, which is not good After this there is the ISM, front and rear SAM and fuse module occasional failures, but all these failures are not like very common so you can find more information about them just on my website To end this, take your time and inspect every damn electronic feature before buying Check for fault codes with an OBD scanner and of course pay attention to other regular things which can break more often like: the well-known keyless entry door handles, electronic parking brake, parking sensors or the window regulators Let’s move onto the possible water leaks into the interior, which can be caused by 2 main magical causes: -First, there are 4 main water drains under the windshield Two drains are under the hinges and 2 drains are in the middle, but mostly just the side drains and the first middle drain can clog causing the water to overflow -Last but not least there are the sunroof drains which can clog There are 4 drains on the regular sunroof, but if you don’t want to remove the headliner then you will be able to access only the front drains So occasionally carefully clean them with some fish tape or edge trimmer line The panoramic sunroof on the other hand doesn’t have any drains, at least it looks like that there are none, but if I’m wrong then correct me in the comments This Mercedes can be equipped with the Airmatic adaptive air suspension or with the active ABC hydraulic suspension -But first the airmatic This is a regular self leveling air suspension which is obviously comfortable, but because of the electronically adjustable shocks you can adjust it from comfort to a bit stiffer sport mode as well + you can raise the car a little with a button on the dash It’s all great and awesome, but there are the well-known air suspension parts which will sooner or later break, so: mainly the air compressor can more often wear out, the air struts can start to leak anytime basically, and rarely one of the air pipes can crack a little and leak All of this means that you should definitely keep extra money to replace at least half of these parts Before buying it’s good to test the air suspension by at least raising and lowering the car a couple of times, check if the car is standing in level, inspect the air struts visually and keep in mind that the suspension should not lower even after a week of sitting -But let’s move on to the ABC active hydraulic suspension which is also comfortable, adjustable and self leveling

To top of that, compared to the airmatic it significantly reduces the body roll in all situations and because of this, the car feels lighter too Again, it’s all great and awesome but the maintenance and repair costs of this suspension are higher than in cars with the conventional airmatic setup Instead of air, this ABC suspension uses hydraulic fluid which is under high pressure The fluid is distributed by numerous lines thru the valve blocks into the accumulators and shocks And the pressure? Of course there is also the pressure, which is maintained by a main pump mounted on the front of the engine And surprise, surprise this pump can be faulty So if you hear various whining, howling or grumbling noises from the pump and you feel a vibration in the interior and especially in the steering wheel at idle-up to approximately 2000 RPM, then most probably the pulsation dampener mounted on this pump is faulty Sometimes the expensive pump itself can be faulty as well Then there are the lines which can crack and leak, so before buying check not only for the already mentioned pump noise but also for leaks from these pipes! And especially check this front hydraulic hose located in front of the engine which can crack more often and dump all the fluid out!!! On the other side not only the pipes, but also the shock absorbers themselves can start to leak However I have to add that mostly still just the before facelift cars are more prone to these leaks because of the age But listen, to minimize the issues with the various components of this complex suspension and to extend its lifetime you should definitely replace the hydraulic fluid and the filter in this system every 4 years or 60 000 km and check the fluid level regularly! Lastly it’s good to know that cars equipped with the Airmatic do have a visible air line on top of the front shocks and cars equipped with the ABC don’t have anything on this place The other suspension components: control arm bushings, ball joints, tie rods so all that usual shit can fail before 100 000 mi, and check for all those usual noises from the suspension I would not consider the petrol engines very unreliable but there are a couple of weak and weaker points which can turn your S class ownership experience into a: one man’s trash another man’s bigger trash experience -Let’s start with something minor and not that expensive to fix Engine mounts! These engine mounts are made from chocolate so they can easily compress, or fall apart completely even before 70 000 mi -Then there is the well-known balance shaft sprocket failure which can occur in cars made to 2007 Mostly the V6 M272 engines are affected, but the V8 M273 engines can have occasionally worn gears as well Because of the worn gear the timing chain gets loose which will cause misfires, an illuminated check engine light with stored fault codes, eventually a rattling noise from the engine and at the end the chain will skip which will most probably destroy the engine -The next problem which affects all of these M272 and M273 engines is related to the complex variable intake manifold Basically a plastic arm on the outside can break or sometimes the plastic flaps inside the intake manifold can fall apart as well, causing various funny issues But for more information about this visit my website Then there are 4 camshaft adjustment solenoids which can leak oil or they can also fail They are located on the front of the engine so replacing them is not very hard, and luckily they are also not expensive Next there are the newer versions of these engines The V6 M276 remained without a turbocharger, while the M278 V8 got 2 turbochargers Interestingly the turbochargers in this V8 are usually reliable, unless of course the car was abused, used only on short distances or it has high mileage However if one of them fails then the engine has to come out to replace it, but that’s just a minor detail So as I said they are usually ok, what is not really ok is, that these 2 engines can develop a short rattling noise at cold start which is often caused by the loose timing chain tensioners Because of this the chain can stretch prematurely, which is not good

So to fix this you have to replace the tensioners and fit this small check valve But if the rattle persists then you have to replace also the camshaft adjusters, which can be faulty, and this step will finally solve the damn rattle! -The next on the list is the massive V12 with two turbochargers It is awesome, it’s powerful, it’s not equipped with direct injection which is good, and there are also no major mechanical problems with it However life is not a fairy tale so the maintenance of this engine is obviously expensive For example, this engine has 2 spark plugs/cylinder so there are 24 of them in total This means that replacing them is obviously a bit more expensive and more time consuming than on a regular V8 This would not be that big of a deal if the ignition coils would not be special and fucking expensive As you can see the ignition coils are built into this rail which means, that if one coil fails then you will have to replace the whole assembly Then keep in mind, that if you buy mainly an older before facelift S600, you have to be ready for various leaks Some random oil pipe can leak here and there, but that’s not even worth mentioning On the other hand what is worth mentioning is a common possible leak related to the turbochargers on each side of the engine of course As you can see, there are 2 lines on the top of the turbocharger This is an oil pipe and the other is a coolant pipe, and the coolant line ending can leak In this case you have to replace only a cheap o ring on the end of these pipes, however you have to remove a bunch of stuff to access them which is time consuming But at least there is no need to remove the engine However it’s also good to know, that if you are like really unlucky then not the o-rings, but the turbocharger itself can leak coolant from the core plug! And in this case you have to remove the engine and replace the whole turbocharger since these plugs are not available separately, but as I said this is not like extremely common so there is no need to make bigger panic The last from the non AMG versions is the S400 hybrid model which has the M272 V6 engine And what about the hybrid system components? Well you can’t expect that they will be that reliable as in a Toyota Prius For example this thing right here is the inverter It costs around 4 000€ and the inverter failures are pretty common The funny thing is that if it breaks completely then the engine will shut in the middle of the road and you won’t be able to start it like never, never after Then there is the hybrid battery which is located under the hood It costs around 8 000 € and it won’t last forever either All of this means that if you don’t want to spend another thousands for the special hybrid system repairs, then just avoid this hybrid version completely Lastly, let’s briefly check out the AMG versions The before facelift S63 AMG made to 2010 has a naturally aspirated 6.2 l V8 The same engines was used in the CLK 63 AMG and in the E63 AMG as well, which means, that it can have the well-known issue with the stretched or completely broken cylinder head bolts This can lead to a serious engine damage if you don’t catch it early, so it’s a good idea to replace the old bolts preventively with the new updated bolts For more information visit my website The newer S63 AMG made from 2010 has a similar engine as the newer S500, so it has two turbochargers and direct injection and it has the same possible issues as the engine in the S500 The most powerful version of this S class is the S65 AMG which has a modified V12 from the S600 model, and it can have the same issues as the engine in the S600 To end this, keep in mind that there is a bigger chance that all these AMG versions were abused, so the risk of unexpected wear and repairs is increased mainly if you buy one, which is not from the first owner From the diesel engines the most reasonable choice is the 3.0 l V6 The reliability of this unit is not bad, so except the usual diesel engine problems it doesn’t have many specific issues But there are 2 issues which are more common and which are worth mentioning: -The first is related to the inlet port shut off motor or the swirl flap motor in other words

This motor can fail, causing limp mode with an illuminated check engine light, but for more information visit my website -The next issue is the famous oil cooler leak caused by the seals attached to this oil cooler The new updated seals are cheap, but that damn oil cooler is buried deep down in the engine, so you will have to remove plenty of stuff in the middle section of the engine to access the cooler Because of this it’s not the easiest job The 4 cylinder diesel engine is generally speaking not the best choice, mainly because it can have more often issues with faulty injectors and with the prematurely worn timing chain On the other side, to improve the reputation of this engine, I have to add that the injectors were most of the time fixed under warranty or under a recall, but the timing chain was usually not The last engine is the big V8 with two turbochargers Listen, this engine can serve you well unless you buy a high mileage car, or a car which was not treated properly But either way, you have to be prepared that because of the bigger complexity and lack of space around the engine, the potential repairs are not going to be the cheapest +except the usual diesel engine problems it can have the exact same oil cooler leak as in the smaller V6, and there are occasionally cases of head gasket failures All the engines are equipped with timing chain which can be usually worn just after 250 000 km, or 300 000 km, except the already mentioned petrol engines affected with the balance shaft horror story, the 4 cylinder diesel engine and the newer generation of V6 and V8 petrol engines, which don’t have the check valves and new tensioners fitted In all these cases the chain can be easily worn even at 150 000 km -Most of the engines are equipped with the infamous 7 speed automatic gearbox All you have to know about it is, that in cars made to 2008 it can have more often issues with the conductor plate -specifically a speed sensor on it fails more often, but sometimes also some of the solenoids can fail Next the torque converter failures are also not uncommon and some mechanical parts inside the gearbox can be more worn too So definitely check for: harsh downshifts in lower gears, shuddering, or harsh shifting in general which are the symptoms of the gearbox issues On the other side from 2009 they improved this gearbox, which means that with regular oil changes it will work for a long time -The older 5 speed automatic transmission is not that fast or up to date as the newer 7 speed, but it’s more reliable Although if the previous owner never changed the gearbox fluid then it can have also issues with more worn torque converter But if the oil in it was changed regularly then it can withstand more than 200 000 km without issues OK and thats the end As the last things I would add that the car has to ride smoothly at all speeds without vibrations or strange whining eventually growling sounds To summarize things up: the best is to buy a car made from 2009, I would avoid the hybrid models completely, and if you are buying the newer twin turbocharged V8 or one of the AMG versions then I would twice as much highly recommend to avoid cars with performance upgrades + It’s good to keep 5000€ for the additional repairs, but if you are buying a V12 or one of the AMG versions then it’s good to keep twice that much money And as usual, if you have personal experience with this car or more information about it, then you can write it into comments, thx for watching!