I have seen this thread, and saw the article before it was even posted here.
Still waiting to see a single newer MB diesel engine in our shop with any major problem. And I see plenty with some pretty high miles:
I have four Sprinters in my care with well over 500k miles now.
The only problems I see are:
occasional sensor (NOx, O2, EGT, or DPF pressure), EGR valve, DEF tank heater, and a couple cracked DPFs (flex section) and if not corrected right away they can leak in such a way as to shoot out a jet of hot exhaust when the DPF regens that melts the DEF injector and line.
Engine proper, though? Nothing. Zip. Nada. No leaks, no noises, no nothing. Oil change with Pentosin 5w40 HP2 (a 229.51 compliant oil) and Mann filter every 10k miles. Alternator clutch pulley once in a while, glow plug once in a while, accessory belt idler pulley bearing once in a while, etc. But these are all just the 3.0L V6 diesel, as the 2.1L 4cyl (like mine) are still too new. But a guy on the Sprinter forum already has over 400k miles on his 2.1L with zero issues, and so far none of the ones I see have had any issues either but the highest mileage one for me is only around 60k. The V6s I see all have 150k+ miles on them before they've needed anything.
Now I cannot say how these engines do in the smaller vehicles (M-class, E-class, Jeeps, etc.) but I would assume if they can push a big box like a Sprinter around for half a million miles they should be just fine with the others.
I did have one HPFP on one of the V6s, around 470k miles IIRC. We just put a new pump on, and it is still to this day on the road.
And I did replace a transmission once on one, it was a 2007 DRW model with a giant vocational box on it. And it had over 100k hard miles on it at the time. That is the only NAG MB trans I have ever seen fail. See a few leaky pass through electrical connectors on them, easily fixed.
I really have no idea what the author of that article is talking about, because I certainly have never seen it. Maybe sitting in all that SoCal traffic is not beneficial, who knows.
I know my experience here made my choice of buying a new Sprinter, in particular with the 2.1L, a pretty easy choice. And it is an amazing little engine. The few people that I have taken for a ride in it are astonished when I tell them it is a 4cyl.
