Completely flat out in a well tuned straight piped 300SD in ideal conditions (flat) I was able to lay it on the 5,250rpm governor on occasion around 109-112mph.
Its really screaming at that speed, feels like flying a single engine plane. And yet....never any problems, sold it at 323k still running fine.
Now my GLK will reach that speed easily at about 2,900rpm with LOTS left to give...and quietly. Crazy stuff. I believe it has the USA 130mph tire-based limiter on it. It cruises comfortably over 30mpg @85 with the A/C on around 2,200rpm
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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)