A casual widely used German taxi which has an awesome V8 engine under the hood. This is the rough description of the AMG version of the well-known Mercedes E-class with the W211 codename.
This Mercedes was available with two engines and two transmissions. Both of these versions give you more than enough power and because of the standard air suspension they are also comfortable enough, so your bones won’t rattle on bad quality roads, hopefully. Although you can experience rattling or creaking sounds from the 2 part panoramic sunroof.
The interior is usually in a great shape even in high mileage cars so all the materials are durable, the seats are comfortable and all of these AMG models are standardly well equipped with various features. Of course the multimedia system is not the newest but there are numerous up to date aftermarket units available on the market.
Obviously, check properly all the electronic features as in the other cars, and pay bigger attention to the following things:
-Test the electronically operated optional multicontour seats, because they can have issues with some of the adjustments which simply won’t work.
-If the car is equipped with the keyless entry feature, then it can have faulty exterior door handles and there are also cases of faulty keyless start/stop button on the shifter-in this case most probably the wires which go to the shifter are broken, so it’s enough to solder them back together.
-Then, some of the wires in the trunk lid wiring harness can break as well-causing faults for number plate lights, 3rd brake light or problems with the trunk lid opening.
-And definitely check for fuel smell inside and outside the car, because there are numerous cases of leaking fuel pump which is located under the rear seats. This issue was in a lot of cases already fixed with an updated fuel pump assembly, but there can be still cars with the older unit. Replacing the fuel pump assembly is not very cheap, however they extended the warranty for this fuel leak to 15 years in the US if am not mistaken, so if your car is not older than this than the dealer should fix this issue for free.
-Door locks can fail as well mainly on before facelift cars and
check if the optional panoramic sunroof is working properly.
As usual check for water leaks in the interior and in the trunk.
-Most of the time only the sunroof drains can cause the leaks, which means that they can be just clogged or the drain tubes can split-in this case they let the water to leak down the A pillars onto the front footwell.
-Then it’s good to check the area under the windshield. It has to be clean without dried out leaves and dirt.
-And lastly there are cases of cracked third brake light plastic cover or faulty brake light seal which can let the water inside the trunk lid.
These cars were available with only the Airmatic air suspension which really helps to achieve a more comfortable ride, so this Mercedes is more comfortable then for example the BMW E60 M5. But the M5 on the other side handles better in the corners.
But back to the air suspension which you should at least test before buying. So raise and lower the car a couple of times and check if it’s standing in level on an even ground.
-The air suspension is getting older and you like it or not, the air strut leaks are inevitable. Which means, that if the car is still equipped with the original air struts from the factory then be prepared to replace them since they can fail at any time.
“If you are too scared of this system then you can purchase an aftermarket coilover kit.”
-The front control arms can be worn as well, but this is nothing unusual so check for all those strange knocking, squeaking or clunking sounds from the suspension.
Let’s continue with the brakes. Now, the older E55 model is equipped with the special SBC electronically operated brake system while the newer E63 version has conventional brakes.
-The SBC brake system was a big innovation back then and even today it is pretty useful, if it’s working properly of course. This system can produce much higher pressure while braking than the conventional brake system which means, that you will always have the best possible stopping distance. However the SBC pump will fail at some point. They say that it has a programmed lifetime of 300 000 brake applications, so after you pressed the brake pedal approx. 300 000 times then you get a fault code for the SBC brake system which means that the estimated lifetime of the pump is over and it should be replaced like immediately. But of course sometimes it can fail earlier as well. Replacing it is not very cheap, on the other side Mercedes extended the SBC brake system warranty to 25 years in the US which means, that the dealer should replace the faulty SBC pump for free.
Generally speaking both of the petrol engines are definitely not unreliable. But of course regular issues with oil leaks for example can occur. Specifically the valve cover gaskets or the oil pan can leak more often and in some cases the rear main seal can leak as well. So check for oil leaks and check also the engine mounts which can be often worn too. But these are not major problems and you can mostly fix them for a reasonable price.
“you have to remove the subframe to remove the oil pan and fix the oil pan leak”
The 5.5 l V8 in the E55 model can have some specific issues like the:
-Intercooler pump which can be faulty, causing the supercharger to shut off. In this case you have to change the old pump to the updated one which is not hard and there are internet guides how to do it. (updated pump number: 0392022010)
-Then there is the supercharger which is most of the time in a good shape, but you should listen for strange metallic grinding or squeaking sounds from it, because the supercharger clutch assembly bearing can be worn. In this case there is no need to replace the expensive whole assembly, since you can replace only the bearing itself which is cheap.
However, rarely the metallic grinding noise can be caused by the rear supercharger bearings which can be worn as well. In this case the biggest problem is, that you can’t buy these bearings separately so you have to buy either a used supercharger or a brand new one which is really expensive. But as I said, this issue is not very common and it usually affects only abused or very high mileage cars.
“If the car has more than 160 000 km / 100 000 mi then it’s good to change the supercharger oil too, yes believe it or not, it has a small amount of special oil in it.”
“After buying you should remove the supercharger belt and the accessory belt to check all the pulleys for the already mentioned noises or excessive play, and the supercharger belt tensioner can be worn too. But if they are quiet and not loose then there is no need to replace them. However if they are worn then you should replace them as soon as possible. Of course you should change the belts as well if they are older or damaged but that’s obvious.”
-The last thing is the crankshaft position sensor which can fail – in this case it will be difficult or impossible to start the engine, but replacing this sensor is not very hard.
The 6.3 l naturally aspirated V8 in the E63 version has basically only one possible but pretty serious issue which is related to the cylinder head bolts.
-Mercedes used not the strongest cylinder head bolts which means that they can slightly stretch or break completely-causing leaking head gasket. In this case you will experience coolant loss due to coolant entering the combustion chamber via the blown head gasket and it will mix with oil. All in all, if you don’t fix this then you will end up with a destroyed engine, but Mercedes updated these head bolts so you can obviously replace them preventively. You either replace them one by one, without removing the heads and replacing the head gaskets – this is I would say the cheaper preventative solution. Or if you already experienced bigger coolant loss and coolant mixing with oil, then it’s better to remove the heads and replace the head gaskets too-this is obviously much more expensive.
This problem is not like extremely common, so there are still even high mileage cars with the factory head bolts. On the other side there are already numerous cases of failed head bolts and some owners just replaced them preventively. At the end it’s up to you. But if the car still has the factory head bolts then you should check the coolant level regularly and if you experience even the slightest coolant loss then first check for leaks, and if it’s not leaking anywhere then you should consider replacing the bolts as soon as possible.
“By the way, if you have this engine then it’s really important to have clean engine oil, so change it after maximum 8 000 km, and keep the oil topped up to the correct level, because if not then you are increasing the risk of problems with the camshaft adjuster solenoids or prematurely worn camshafts. (symptoms of faulty camshaft adjusters: possible rattle at start up, misfires, possible check engine light)“
Both of these engines are equipped with timing chain which is not famous for premature wear so it should be in a good condition.
The E55 version is equipped with the older 5 speed and the E63 version has a newer 7 speed automatic gearbox.
Both of these transmissions are fairly reliable, although the older 5 speed is considered as the more reliable since it was designed to handle 1 000 NM of torque. But you should keep in mind that the early E55 models made in 2003 had a faulty radiator design which means that the radiator can allow the coolant to mix with the transmission oil which will obviously kill the gearbox over time. Cars made from 2004 do have updated radiators, so if you want to buy a car made in 2003 than it’s good to consider replacing the radiator preventively even if it’s still not leaking.
Problems with the faulty conductor plate can also occur but mostly on the newer 7 speed gearbox. All in all, definitely check both of the transmissions before buying, change the oil in them and check them for leaks because the low oil level will kill both of them, obviously.
To summarize things up: it’s better to buy a car made from 2004, it’s better to avoid cars with any kind of performance upgrades, buy only a car with proper maintenance history, and definitely keep some money for the additional repairs. (+find a good independent specialist)
As usual, if you have personal experience with this car or more information about it, then you can write it into comments!