[SDGT3]

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.

A diesel engine will require more preventative maintenance as you described, such as fuel filters, but AdBlue is extremely cheap in your local auto parts store. The highlighted issues your family member is having have parts that are independent of gas or diesel engines such as a starter, radiator, fuel pump, transmission, ball joints and shocks.

I'm a relatively new believer to having diesel engine vehicles. My ML is only 1 1/2 years old and it's a garage queen with the exception of towing and long family road trips. However, I just bought a VW Passat TDI as a daily driver and have nearly 4000 miles in just 3 weeks! I can tell you, I'm love my MB 6 cyl. Bluetec better for it's overall power and how quiet it is over the TDI, but it's hard to beat ANY diesel for mileage as well as instant power in the way of torque when you need it.

The same preventative maintenance is required of a VW TDI as the Bluetec, but the everyday tradeoff of economy and power is well worth it. To say nothing of the (as I write), the lower cost of diesel fuel in the southwest vs. regular grade gasoline.

 

[SDGT3]

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.