Mercedes E-320 Diesel
 

Week ago I went to a dealer and saw a Mercedes Benz E-320 Diesel An I liked the car and I am thinking to buy it.
As I never got close to a diesel car like that one, I would like to hear advice from people of this site. I read comments that the car is a "must to have" and others comments like "expensive to maintain". These cars are for sale in Dallas - Texas where I live and they are costing around 11,000.00 Dollars.
I have two old 1982 300 SD and these two old cars never failed on me with more than 390 K miles. Now as I never had car like E-320 I don't know how much problem free are these cars. The one that I saw this past week is a 2006 and it has 150 K miles and the other one has a 220 K miles.
So your advice as Mercedes owner will be very important.
Thanks.

My advice is to only consider advice from people who actually own the car.

My experience is that they are reliable, easy to work on, and no more expensive to repair than any other car I have owned. They are very impressive cars to own and drive.

A couple years ago, a friend of mine bought an '07 E320 Bluetech with 26,000 miles on it. They thoroughly love that car. It gets upwards of 40 mpg on the highway, and drives like a dream. The car is also very powerful. Other than regular mantainance, it has had no issues. My vote is that you buy it......Rich
EDIT: not originally realizing that nyko46 was looking at a 05-06, I now know that the '07 has the V6 Bluetech, and the earlier W211's had the CDI. They are both great engines, and I would not hesitate to buy one if I could afford it.

Here's a buyers guide thread for that model. It discusses maintenance, common problems, etc. http://www.peachparts.com/shopforum/diesel-discussion/366604-2005-2006-e320-cdi-buyers-guide-common-problems-roll-call.html

CDI shopping spreadsheet

It was all the cars I could find offered on the internet from March through June 2015.
On row 338 you will find a summery of the % of cars that came were each of the options offered.

Yes guy, I ended up buying the car. It is a 2009 Mercedes Benz Bluetec - V6 - 24 Valves - Diesel engine. The has 151K and had only one owner and it is in a excellent condition.
I drove it home and it has a smooth ride and it is extremely comfortable.
Up to now I am happy with the car and also with the purchase that I made.
Thanks all for the advice's and now is only take care of the car.
Thanks

You have the OM642 V6 engine instead of the OM648 inline 6 that was in the 05 and 06. I have a 642 in my wife's ML.

The 642 has a bad reputation for a couple problems that are not fatal just really annoying.

- the infamous oil cooler seal leak. There is an epic thread on this issue on this site. Practically everything above the heads have to come off to repair this.

- the intake duct to turbo joint leaks condensed blow by. This drips down and makes you think you have an oil leak. But you can tell the difference especially after it dries. The red ring gasket is in the $20 range. The black 'y-pipe' is $500 due to the two MAF sensors included in it. Of course the black pipe is the problem most of the time because people force the tube on and off when changing the air filters.

- this blow by drips down into and fries the 'swirl flap motor' which changes the geometry of the intake tract under different operating conditions. Since this is an emissions system part it is monitored by the ECU. If it fails it will throw a code and also put you in limp mode. Achieving 45 mph will be a challenge at this point. The temporary fix is to put a 4.7 k ohm resistor between the two center pins on the connector and leave it unplugged. This fools the system after you clear the code. The permanent fix is to replace the swirl flap motor. Since the turbo has to come out, and once you remove the swirl motor you are in pretty deep, you might as well do the oil cooler seal job at the same time. I am in this situation and waiting until it is not 98 degrees every day to take this on.

- the cam position sensor is located on the top of the passenger side cylinder bank. If it starts failing it will throw a code. If it fails totally the engine will not run at all. I would replace this on principle if the engine has more than 100k miles/10 years on it.

- the worst complaint I have is that this was designed to be a multi vehicle application engine. It is found in E and M class, Jeep CRD uses this engine, (edit: also used in Sprinters), and Pacificas in Canada and Chrysler 300s in Europe. As a result it is like a rubber band ball stuck in the engine bay so that it fits the footprint. This makes things harder than they ought to be to work on the engine.

Added: when searching online, look at forums for these various other vehicles for hints on this engine. The Jeep and Sprinter guys are quite active and I have found a lot of info there.

- see these threads I wrote, you may find them helpful:
http://www.peachparts.com/shopforum/diesel-discussion/378195-om-642-camshaft-position-sensor-replacement.html

http://www.peachparts.com/shopforum/diesel-discussion/367295-om642-glow-plug-replacement.html

http://www.peachparts.com/shopforum/ml-gl-g-wagen-r-class-unimog-sprinter/351623-om642-service-tips.html

And here is the oil cooler thread

http://www.peachparts.com/shopforum/diesel-discussion/363973-journey-into-infamous-om642-oil-cooler-leak.html?highlight=Om642+oil+cooler

From what I have heard, these are otherwise very good engines, major torque producer, in an E class that thing has to be a total rocket. At least in a 07 or later E class you don't have the SBS brakes.

I am actually starting to look at these models myself. There are plenty of these in the market in the low teens range.

The oil cooler leaks were on the early year models with the old compound seals. The newer models with the new compound seals will not have that problem.

I thought I had read that they did not figure this out until 2010 so the 2007-2009s got the (bad) orange elastomer seals and the 2010-up got the (good) purple Viton seals.

Well I just got the car this weekend and as far I checked while in the dealer park I saw no leaks and no signs of oil allover the engine.
About the leakage from oil cooler, my two 1982, 1984 300SD have this problem.
I will keep an eye to see if anything like you guys wrote happens to my car.
I noticed that the previous only owner had the car maintained by a MB dealer in Texas and the Carfax is showing all the dates of the services.
I only don't know when was the last motor oil and transmission fluid changed.
Not knowing the last change date, should I change oil and transmission fluid very soon?
Does this car uses synthetic oil or not?
Thanks for your comments.

The oil cooler on the OM617 is a mini radiator (oil to air heat exchanger) next to the main radiator. The OM642 oil cooler is a oil to coolant heat exchanger on top of the cylinder head. It is a module that seats on ports in the head tied into the oil and coolant passages. There are two figure 8 gaskets that cost about $15 that leak. Changing these gaskets requires major disassembly.

Oil must meet MB spec, I run Mobil1 EXP X1 0W-30. It's about $10/qt and you need 9 quarts. Look online for best deals. If you do not use this special oil it will ruin the particulate filter. Also there is a proprietary oil filter, I do not use anything but OE filters from the dealer. You will need a special oil filter cap tool for OM642, check EBay. Also invest in a MityVac 7201, makes it unnecessary to get underneath when changing the oil.

Check the display in the dash, it will tell you when the next time the oil needs changing. Navigate to the odometer screen then scroll to the "Service x in xxxx miles" display.

Transmission fluid must use special MB fluid for 722.9 transmissions. It is like $15/liter and it takes 8 liters or so. And you have to raise the car at all 4 corners and pump the fluid into the pan from below - there is no dipstick.

Not trying to burst your bubble but this is not in the same league as a 617 as far as maintenance - no running down to Walmart for a couple jugs of Rotella and generic Dexron II.

Also this vehicle according to MB will not survive being run on alternative fuels nor greater than B5 blends. (Although GregMN will tell you different.)

Jay_bob;
Then this MB is not so friend to work on like those old 300's ?
Well I am a good DIY guy and I do not expect to be beaten by this car. All my other's old MB never beat me. Anyway, I have this philosophy: living and learning.
By the way, how often these cars give problems for owners and how often they have leaks and other similar problems? My wife's Suzuki Forenza in less than three years the valve cover seal had to be replaced. The seal get bridle (hard) and start leaking oil from valve cover all way to the engine and from there to the garage floor.
I have most the metric tools to work on my MB cars and Suzuki but I hope not to get so many problem with this E320.
I appreciate your comments, they are very helpful.

Basic maintenance is not so bad for a good DIY. Just not as easy as the older cars, much more technology jammed in a smaller space.

If you already have metric tools, be sure to add a good set of internal and external Torx sockets to your collection. Get good ones (Lisle, Snap-On, etc), not the unofficial Chinese copies from Harbor Fright. And a pair of Oetiker pliers for the fuel line clamps.

You will need at least a basic OBDII reader to deal with check engine lights. If you have the funds get a Xentry clone from eBay, it is what the dealer uses and it makes it point and click to find out what is wrong and directs you how to fix it.