COAL: 2012 Mercedes Benz E350 BlueTec – A Different Type Of High Mileage Benz


[Buy a car just before Christmas, you get a big red bow on it.]

Our 2008 Dodge Nitro R/T (COAL) served us well for over 5 years, but (my now husband) James was ready to try something new.   He had a desire to own another diesel powered vehicle, but the available SUVs were either too expensive or didn’t impress him enough to purchase.  The Q7 TDI had been high on the want list, until a drive in a Certified Pre-Owned Q7 just left him feeling ‘meh’ about it.  I honestly don’t remember how we ended up there, but one day we found ourselves at Mercedes Benz of San Diego taking a test drive on a Certified Pre-Owned 2012 E350 Bluetec.  It wasn’t an SUV.  It wasn’t flashy like the Nitro, Range Rover, and S420 was before it.  Something about it clicked with him though, and a few hours later he was driving off as the new owner.  It was the combination of everything he missed about our previous Mercedes along with the desire to have a diesel powered vehicle.


[Photo courtesy of]

First off, the engine.  It has a 3.0L turbo diesel V6 engine that makes only 210 horsepower.  That’s not the number to impress, it was the gargantuan 400 lb-ft of torque.  According to Car & Driver, it’s more than the E550 V8 torque rating.  While not as quick or fast as any other E-class sedan, it was equally as quick as the Nitro.  The best part about it is the power delivery.  There is just the slightest perception of turbo lag as soon as you put the hammer down, but then it happens.  It pulls like a freight train and doesn’t stop.  It is so linear in it’s delivery, and sucks you into the back of your seat.  It is very easy to reach illegal speeds before you know it.  This was very reminiscent of our previous S-class Mercedes.


It’s mated to the same 7-speed automatic that’s available in most Benz sedans now.  Once at speed, it shifts smoothly under normal acceleration, and with a good solid shift when it is floored.  The one irk with the trans is that sometimes there is a thunk when it shifts down to 1st gear when coming to a stop.  It also has paddle shifters on the steering column.  At first I thought it was silly, but since the transmission selector is on the column it is helpful to have some way to manually select the gears.

What about the diesel noise?  Inside the car you can’t tell that you are driving a diesel.  If you were to sit in the Bluetec and a regular E-class back to back, you might notice a slight bit of diesel noise.  Might.  Without the comparison, you don’t notice it at all.  It is the second quietest car we have ever owned, only behind our S420 (COAL) (with the double-paned windows).  Even standing outside of the car while it is running, it doesn’t sound like the clackety clackety that most people associate with a diesel engine.  It is smooth and quiet.  The only exception to this is start up on a cold morning, that’s when the clatter is truly audible.


[41 mpg while averaging 74 mph.]

Then there is the fuel economy.  While most gasoline powered cars struggle to reach their rated fuel economy (as listed on their window stickers) in every day driving, we routinely exceed ours.  By a lot!  The E350 Bluetec is rated at 21 city/35 highway.  In mixed driving around town, 30 is easy as pie.  On the highway at a cruising speed of 80-85, easily hitting 38-42 mpg.  This is the first car we’ve had that we routinely brag about the fuel economy.  Sure, you can get that kind of economy in a compact Kia or a hybrid, but this is while cruising in the lap of luxury in a full size car.  The icing on the cake is the price of fuel.  When we first purchased the car, diesel prices in southern California were on par or slightly more expensive than premium gas.  The last year or so, diesel has been anywhere from $.40-$.75 cheaper per gallon.  This doesn’t translate out of California, however.  On trips outside of CA, we found diesel fuel to be significantly more expensive compared to gasoline.


Inside the car is a great place to spend time.  The seats are firm and supportive.  The driver’s seat has an active side bolster feature.  When those are turned on, the side bolsters will inflate to hold you in position when g-forces are detected.  On the low setting it works well, on the more aggressive setting your kidneys are being punched by the car.  Satellite radio, Nav system with traffic data, bluetooth, HD radio, bluetooth music streaming; it has all the bells and whistles.  It even has a weather map (subscription required) for the entire US.  Ours is also equipped with the panoramic roof.  Two big glass panels over the top of the interior, the front one is a big sunroof.  You can retract the sunshades and let the sun shine in over the entire interior.



[Sitting in my grandmother’s driveway after a 3-day eastbound blast across the country.]

Last year, my grandmother passed away.  We live in San Diego, and she was in North Carolina.  Last minute plane tickets for my husband and I to get there were going to be outrageously expensive.  The range of the Benz and the associated costs made driving a viable option.   We decided to spend the time and not the money and elected to do the drive.  It was three days there (San Diego to Amarillo, Amarillo to Memphis, and Memphis to Graham, NC).  Three days to visit with the family and the funeral, and then three days back (Graham, NC to New Orleans, New Orleans to Las Cruces, NM, and Las Cruces, NM to San Diego).  For the first time in 18 years, we both got to see our mothers on Mother’s Day.  Mine in North Carolina and his in New Orleans.  We were also able to cross off a bucket list item with a drive across the country.  It was also on this trip, on a deserted stretch of freeway that we decided to see how well this car performed at autobahn speeds.   It didn’t disappoint.


[Sssshhhh, don’t tell no one.]

Trips like that are what this car is built to do.  It ate up the miles, very rapidly.  It hunkered down and cruised so effortlessly.  80-85 mph and it feels like you are riding on a pillow.  It’s not wallowy, it is very connected to the road.  It cossets you on the freeway.  The seats are super comfortable, and the driver’s seat also has a massaging feature in it that helps.  You would think after that many miles behind the wheel you would be exhausted.   I was more tired after driving the Mustang for 4 hours compared to that entire cross country trip in the Benz.

There are a few downsides to owning a diesel Mercedes, but we were well aware of them going into ownership.  Maintenance costs do tend to be a bit higher.  Oil changes for diesel engines require more oil than a gas powered engine, so there is the added cost there.  Offsetting that is another oil life monitor, so the oil changes happen at less frequent intervals.  We occasionally have to refill the urea fluid (called AdBlue by Benz).  We’ve done this ourselves a couple of times to save money from having the dealership do it.  Again, the car notifies you when it is time to do this.


[At the front entrance to James’ high school.]

There have been a few items that have needed to be replaced, and they were done under warranty (either factory or the extended CPO warranty).  The interior wood trim bleached out by the sun, and developed a whitewash look to it.  It was actually like this when we bought the car, but didn’t realize it was a problem until we saw the wood trim in another E-class.  Turns out this was a common problem in this generation of E-class, and it was replaced.  It also developed an oil leak, and this was at the oil cooler.  The entire oil cooler was replaced under warranty.   The knob for the Command info-tainment system broke and stopped rotating.  Again, another common problem with this car and it was also replaced under warranty.  One problem that hasn’t been corrected yet is the leather on the center console is starting to crack from elbow wear.


There has been an issue that appeared with the transmission, twice so far.  As we are driving down the freeway with the cruise control on, I noticed that the car was losing 5-10 mph while going uphill.  As we would crest the hill and start down, the car would move back to the set speed.  Thinking that the cruise control was going out, I turned it off and continued on.  As I drove, and we diagnosed more, we determined that the transmission was refusing to downshift.  When we exited the freeway near our house, the transmission finally lurched down all the gears to first as we came to a stop.  During acceleration, upshifting was fine but it refused to downshift until a stop forced it to.  We scheduled a visit to the service department for the next day.  After sitting overnight, the car did not exhibit the behavior and drove normally.  The service department couldn’t replicate it either, and no codes were thrown.  It happened once again several months later, but again as soon as the system reset (turn the car off and back on) it stopped occurring.  That was the last time it has occurred, and that was about 18 months ago.  I now have this little nagging thought in the back of the mind that someday soon the transmission going to eat itself.



[Hey Alanis, is this ironic or just dumb luck?]

This past summer, something potentially catastrophic happened.  I now refer to this as the “Valdez Event”.  While driving down the freeway the A/C stopped blowing cold air and would not go above HVAC fan setting 3.  We try to turn the climate control off and on again, maybe it just needs a reset like the transmission.  Then the warning of “Check Engine Oil At Next Fuel Stop” appears in the center display.  Something was clearly not right and James starts to make his way to the next exit.  Then we noticed the oil smell coming through the vents, and the faint blue smoke trailing behind the car.  We exit quickly and turn the car off.  The entire left side of the car is covered in a spray of oil.  Under the hood, oil has sprayed everywhere from the O-ring on the oil filter canister.  When the flat bed finally hauls the car away, there was a huge oil slick underneath the car.


[A German car in it’s natural habitat?]

We assumed the worst had happened.  Something internally caused the oil pressure to build and it finally escaped from the weakest link, that o-ring.  The service department at the dealership cleaned all the oil from the engine and chassis.  Their report back was that the O-ring had not been installed properly and it failed.  After refilling the car with oil and running the engine, no other apparent damage had been done to the engine.  Thankfully we were paying attention and got the car stopped and turned off while there was still enough oil in it to keep everything lubricated.

Another side effect of the “Valdez Event” was the front suspension.  Apparently coating everything in hot engine oil isn’t good for parts of the suspension.  During low speed cornering and going over bumps, the front end started clunking and creaking worse than my 77 Aspen with 360K miles on it.  Internet forums to the rescue, or so we thought.  The basic symptoms pointed to a part of the front end suspension starting to fail.  Dropped it off at the dealer and they found several bolts were loose.  They were all tightened to specs and it has not made a peep since.


Has this event shaken our confidence in the Benz?  At this point, it is still too soon to tell.  James has been doing a lot of driving for work, and has just recently crossed the 100K mile mark.  The Benz is still under the extended CPO warranty for another 30K miles or so, which does bring peace of mind now that it is a High Mileage High Mileage Benz.  When the warranty is getting close to running out, we will then figure out if we want to keep driving it or swap out for something new and different.