I've had a 2015 GLK250 with the OM651 for the past 13 months/ over 11,000 miles so far and its been great! Mine is just about to roll 80,000 miles. I did experience DPF failure at 78k but it was covered under emissions warranty. I suspect the car did a lot of idling in traffic or the previous owners may have used a non DPF rated oil. (it was owned by a company in Chicago) I currently use 5w30 DPF rated low ash (liquimoly) oil and suspect the new DPF will last a long long time....so its real low on my worry list.

Servicing it is easy as can be since its an inline 4, everything is easy to get to. I've done several service items like trans fluid, oil changes, fuel filter, air filter, cabin filter. Has never left me stranded or had any engine or trans related issues. (also none in its history before me)

The torque is incredible....as are the MPGs!

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)