Experience with Sprinter Class C's

I own a 2006 GMC with a Duramax diesel engine, pre DEF. When diesel fuel lost much of the sulphur content it also lost much of its lubricity. That was important to the diesel engine fuel systems. Each tank full I add a few ounces of either Lucas fuel treatment,Opti lube or MM oil. Recently I fueled up at "pilot' and they are selling Bio-diesel. Well, 100 miles later I have a check engine light, a "water in fuel" warning ,that I have never seen before, and the truck was not performing as usual. A call to a diesel truck shop buddy and he recommended the Lucas top cylinder treatment be added to the fuel. I borrowed a scanner, erased the code and all is well. Bio-diesel, maybe being less expensive, is not my engine's friend. I personally would not own a MB diesel in a motorhome. The fuel savings are just not worth it. I did own a 85 five cylinder sedan and anything that had MB on it was costly to purchase.
i enjoyed reading the post about the 47 MB the poster owned and the stories concerning repairs. As far as the comments regarding how hard the machines were used, well, that's what they are designed for, to be used, run and run some more. A V-10 may inhale gas but it is easy to maintain, any one calling themselves a mechanic can maintain and parts readily available. Friends had 495K on one truck and over 300K on another. One truck was totaled so he gave me , and recommended I carry, a few different sensors and also some spare ignition coils.