I had the same dilemma about a year ago. I have been wanting to try a diesel for many years and since MB built the best diesel motors I thought I would give BlueTec a go. Then I started thinking about it and putting the pencil to it. First, the mileage difference is considerable between the two (some report up to 10 miles per gallon better with the diesel ML). That is the good news. The bad news is that where I live here in Texas gas is king and diesel is usually between .25 and .40 per gallon higher. Also, the BlueTec costs more to purchase than the gas version. Frankly, none of that bothered me and if I really wanted a diesel I would have bought it regardless of the money factors.

I guess my decision to go with the gas version was based on need more than anything else. I drove both and I liked both versions but other than the low end grunt of the diesel I noticed no real difference. I don't haul or tow anything (don't even own a hitch). If I did I would have bought the diesel because although both versions are rated to tow the same amount, the feeling of towing would be effortless with the diesel motor. I trade every few years so the long term benefits of a diesel engine would not come into play. I never put more than 50,000 miles on a car before trading so that is another factor since a diesel is just getting broken in at that point. I also do very little long range highway driving - that is where the mileage factors and low rpms of effortless cruising that a diesel provides would have been a benefit, but not for me. Etc, etc, there just were too many diesel strong points that had no relevance to my kind of driving - so why pay more up front and more every time I fill up? I simply could not justify it. If those strong points had been beneficial to my situation I would have jumped on the BlueTec in a heart beat.

I guess what I'm saying is buy your motor based on your needs. Determine the attributes of both engines and see if those attributes are things you can use and will help your type of driving situation. Then consider all the money factors involved. Chart it all out this way and you will almost always have a clear winner. In your case, if you lease like you did your Lexus and your lease is short term, you may not have your car long enough to reap the true benefits of a diesel anyway.

 

Thanks for the reply yes I will lease for 36 months I like a new vehicle every 3 yrs. From what I have been reading in the reviews I am getting the impression the diesel feels much more powerful. Of course I need to test drive both.

 

We went with the diesel. At first I wasn't sure if it was the right decision but now that I've had it for 4 months I'm now positive that it was right for us.

We have a vacation home in the mountains and it's amazing how the diesel takes the steep hills with ease. My previous car was a Porsche Cayenne 6 cy and while it had the power to drive up the mountain road, the RPM's were significantly higher. The torque on this diesel is amazing.

 

We went with the 2013 diesel because we tow and the bluetec makes easy work of it. The higher MPG is also a plus. Ironically, the price of diesel has been going down at least in Southern California and Arizona where we do most of our driving. Diesel is now on par with regular gas and Premium which is what the gas version of the ML will require is .25 more per gallon.

If towing is not a consideration and better mileage is, then the 2014 ML Bluetec is what you may want to consider. Apparently, MB is foregoing the V6 diesel model for a turbo charged 4 cyl.

What you'll probably experience from seat of the pants test drives is the Bluetec having V8 like launches from a standing start. The gas version won't feel as fast from a dead stop, but both will feel equally comfortable on cruising speeds. The bluetec will be noiser than the gas engine at a stop light, but not much.

Although the bluetec is $1500 more when new, the residual will hold better than the gas engine.

 

If you are leasing then pay less attention to the $1500 MSRP on the window sticker and more attention to the lease costs. Think you will see more than that $1500 recovered on exit.

If you have never had a diesel, then perhaps you should try one. Thats the only way you'll really know. Believe all M-class BlueTEC come with 4MOTION. If you really must have 2WD then gasoline for you.

Say what you will but the M-class is a truck. Trucks should have trailer hitches. Its about $550 from the factory but over $2000 to retrofit. Perhaps I'm biased because the only reason I bought my W164 was for towing. Of course I use it for other things but my Prius can not tow my toys.

EPA says 24 MPG highway for my 2009. My first (4) 500 mile days averaged over 29 MPG with cruise control set at 70 MPH. And measured at the hose, calculated with calculator not the dash display's Fool Computer. The Fool Computer wasn't all that far off displaying 31 MPG for 29 actual. But then this Christmas I thought to repeat the same trip at 60 MPH and had a 1017 mile average of 35.4 MPG showing. Only 31 MPG with calculator. My 10 mile commute delivers 22 MPG on the same route and speeds as Prius gets over 50. Takes the BlueTEC about 5 miles to get warmed up and MPG stabilized, but it blows heat almost immediately. Must have an electric heater.

With open motorcycle trailer MPG drops to 21 at 70 MPH. Big 7x18 tandem axle utility trailer sucked it down to under 12 MPG at 65 MPH.

As for cost of fuel, premium is roughly on parity with diesel. Diesel prices change slower so don't make a spot judgement, must average 3 or 4 months. Many say their ML350's run fine on regular if one is not a jackrabbit.

Today's best prices locally are $3.299 for regular, $3.619 premium, and diesel $3.799. Diesel was $3.849 when regular peaked at $3.599 a month or two ago.

 

Where I live diesel and premium run about 4.20-4.40 a gallon and 1500 price diff ends up probably around 600 when you factor in discounts and the lease residual. I am leaning to the diesel it will be 2 firsts for me an MB and a diesel?

 

gas vs. diesel

Tough choice. This old post was my rationale for ending up going gas last year:

http://www.benzworld.org/forums/w166-m-class/1653684-ml350-bluetec-not-bluetec.html#post5259788

Rumor is that ML will only be available with 4-cylinder diesel next year, so getting the six this year might be smart if you're leaning that way.

 

Rumor is that ML will only be available with 4-cylinder diesel next year, so getting the six this year might be smart if you're leaning that way.

I might like a 4-cylinder diesel even better! There is no reason it can't be just as powerful as the V6. And hopefully should be easier to service. I think if I was purchasing a Sprinter I'd rather have the older I5 than the newer V6.

 

Even though I'm a big fan of modern diesel engines, the gas W166 is a blast to drive, I am surprised how peppy it is from the start and the power delivery is so smooth, much, much better than my 10' W164. Imo, BT was a no brainer in the W164 but on this one its a tough decision.

 

I have the diesel and it is a joy to drive with great power! Overall with the urea cost the diesel probably cost about the same as gas per mile to drive. Diesel fuel where I am is less than premium (today). These new MB diesels are nothing like the old sluggish, clattering, soot sputters of the past. They are quick off the line with great torque. The BluTec's are all wheel drive so offsets the sticker difference if you want that feature. There are no cons for me. Go drive both and see what you think.

 

The gas W166 ML350 is very peppy off the line, accelerates fast and power delivery is very smooth, I am surprised how good this engine is coupled with the 8 speed auto transmission. No need for the strong low end pull of the diesel version IMO.
On the other hand, Diesel vs Gas in the W164, diesel hands down! I absolutely hated the gas version on that model.

 

Not sure if this angle is correct, but the 4 Cylinder ML250 Bluetec got up an incline of atleast 50 Degree's ++ with ease. The Diesel is extremely refined, but at the end of the day, Petrol (or gas as you Americans call it aha) is the best, due to it being the fuel of choice in the ML63 AHAH

 

I love diesels. To me they are just the better engines out there. While they cost more up front they also hold their values better, while fuel generally cost more they go further then its comparable gas counterpart, the power delivery is smoother and stronger, they are a lot quieter then they used to be but still have just the faintest clatter at idle. Here is a link showing gas mileage and cost between gas and diesel. Yes I know its full size trucks and towing but gives you an idea at how much better they are. Towing Fuel Economy Infographic - HitchAnything.com

 

Consider how many miles can you go in 1 full tank of fuel. Why ? Most local grocers (Kroger's and Giant Eagle) - give us up to $1 (used to be $2) off per gallon of fuel. Since the diesel ML can go almost 2x the distance, that means - you can maximize your fuel points. If you dont know what Im talking about - here is a link.

Kroger

But if you are the type of rich person who just dont care about gas prices - then get the ML350 or AMG. :surrender:

 

Sadly such fuel discounts are illegal in some states, such as Alabama. However I can buy groceries in an Alabama Kroger and fuel at a Kroger outside Alabama using my points.

Federal fuel tax on diesel is $0.06/gallon higher than for gasoline. Some states such as Connecticut really stick it to diesel with $0.294/gallon in additional taxes.

I don't like to buy diesel in Indiana because most stations advertise "exempt" prices without 7% sales tax. Their strategy succeeds being over most consumer's heads. Too confusing for public reporting fuel price sites to distinguish between exempt and not. People just report the price they see on the sign. Fuel price sites which use credit card transactions get confused by Kroger's discount. Somebody buys fuel with a $1/gallon discount and thats what gets posted.

 

I love diesels but when it came to leasing a new ML the "money factor" was better for a gasoline version. And even though the diesel gets better mileage, no more than my wife and I drive, we come out ahead with gasoline.

If you are going to put a lot of miles on your ML then diesel might be worth it.

By the way, this is our second ML and the gasoline engine is great. It has lots of pep and moves a relatively heavy ML down the road quite nicely.

 

The 350 diesel also moves the heavy ML down the road quite nicely. The other big, and perhaps even more desirable, feature is the higher torque of the diesel. It is definitely MUCH better for towing, and will out pull my 5 liter, 300HP V8 MB G500 any day of the week.

 

Diesels have so much torque, if you tow or drive in areas with high altitude the diesels/turbo engines have an advantage, the power loss due to air density in higher altitudes is compensated with a turbo engine.

Been having both diesels and gas engines, the main thing is to be able to change the driving style as the diesel you need to let working on the torque, not high revs.

We chose a gas this time, we do not tow and live in flat FL

 

I think you begin to consider purchasing a diesel when -- if not for the diesel option -- you would only have considered MB's 8-cylinder for your ML. For me, that's the real comparo -- not between the two 6s.

 

I have MB's 8 cylinder gasoline in a G500 and the 6 cylinder diesel in a ML350BTC. The towing capability of the diesel is FAR superior to the gasser.

 

I've had both, and a couple of other diesel's over the years. It really depends on whether you need it for towing or not and how much you drive.

A CDI is complex engine with a turbo, inter-cooler, urea injection, running extremely high injection pressures, etc. Other than the balance shaft issues on earlier models, the gas engines are more reliable, simpler and less expensive to maintain. Other than oil and filter changes, the gas engine will go almost 100K miles with basic maintenance. The diesel is expensive to service because it needs fuel filter changes every 20K miles, ad-blue, etc. The fuel filter and air -filter service is expensive because it's a 1 hour job or more to get at the parts. A complete diesel service is $800-900. Diesels are also notoriously hard on batteries. Like the fuel and air filter, they are also conveniently located......under the passenger seat under the carpet.

I have a 320CDI. When I replace it, I'll get a gas 350 since we drive about 10K miles a year. The diesel pulls strong once it's fully warmed up. Short distances in cold weather, you have to take it easy and it's way down on power. One more thing to watch is fuel contamination. All you need is one idiot to put gas in a diesel at a full service station or a family member not paying attention and you've got a $5000++ problem not covered by the warranty.

 

I did a bit of research before ordering a BlueTEC. It will be my first diesel so, I do not speak from personal experience. However, based on what I've read the BlueTEC the highest resale value. A diesel is a more expensive engine because it has to be made better to withstand the higher pressures. A diesel is obviously more efficient but rather than compare the fuel economy to the gas-350 the better comparison should probably be to MB's V-8 --e.g., the diesel is getting about 10 mpg more on the highway. Diesels are renown for their longevity. From what I understand there is very little difference in service costs over the life of the car --e.g., there won't be a need for a tune-up at 100K miles. Meeting the blue state regulations to have a 50-state car may skew the service cost stat in favor of gas engines but still, with the diesel you do have the cleaner car. It definitely will be difficult to pump regular gas into a diesel but I suppose anything is possible.

 

I agree that Blutec's have a high resale because of fuel consumption and are generally a good choice. It's just some people I find are too fixated on fuel consumption and don't consider other costs. My father in law was one of them. He just about died when his 2010 Blutec service at 40K miles cost over $900. I told him buying an MB diesel to save fuel is like buying a Rolex to save on watch batteries. Drive it because you love the truck.

I'm not sure the new MB diesels will last longer in general. MB's today are not designed to last like the old ones. A family member has a 2007 CDI with 150K highway miles. He's meticulous with service and he's selling his truck this spring - too many repairs; new starter, radiator, fuel pump, injectors, glow-plugs, oil seals, rebuilt turbo, new transmission, new ball joints, struts and new Airmatic shocks ($1000 each), sensors etc. etc. He has over $12K of receipts. By comparison, I know at least three people with over 300K miles on their VW TDIs that have had a LOT less trouble. I recently sold my 2003 C320 wagon at 100K miles out of frustration and disgust. We have 8 MBs within my extended family. I could tell you horror stories till the cows come home relating to poor design, quality and service. After driving MBs for over 17 years, I bought a 2013 Hyundai Genesis as my daily driver because I wanted something that goes in for oil changes and doesn't break my wallet. I'm looking for a mint, low mile, 1989-1990 420SEL to drive in the summer/weekends to get my MB fix. These were truly great cars.

Pumping gas into a diesel is easy, since the filler neck opening is larger than for a gas pump, at least here in Canada. Because MB CDIs run so quiet, its easy to miss it's a diesel. There's a sticker in the fuel door, but that's about it. When you pull into a gas station with a Dodge Cummins pickup, everyone knows it a diesel - probably because they cannot have a conversation with you until you turn it off. It's happened to two people I know over the years. The damage is extensive, to point that one of the main problems is metal shaving contamination in the fuel system.

 

Pumping gas into a diesel is easy, since the filler neck opening is larger than for a gas pump, at least here in Canada. .

I can't speak to Canada, but here in the US the fuel neck has a safety flap. If the fuel nozzle is too large, it won't go into the neck. If it's too small - as in an unleaded fuel pump, the safety flap won't open to allow the nozzle in the opening. Many a case of a retailer putting an unleaded nozzle on the auto diesel pump thinking it will work because it's smaller. NOT!

 

As far as my experience goes, I have owned my 2013 ML diesel for fifteen months and it already has 20K miles on it, most suburban driving. It gets 23 miles mpg around suburbia and 26 mpg on the highway (and I drive very fast on the highway). I think diesel is the ONLY way to go for SUV driving, carrying cargo, shopping, short trips with lots of stops, etc. A nice touch is that a diesel engine heats up so much faster than gas, and after this winter that was most appreciated (as was the heated steering wheel and seats).

My only complaint is the irritaing seat belt chime which starts to ring again after a stop in the car (at a light, at the bank window, at the school). I wish the chime would ring only at the first ignition of the engine and then stay quiet. Yes I wear my seatbelt, but not every time the car is moving.