I love the sound of my 617 at about 75mph, its just a smooth hum, and it does it without any strange sounds.....such as those our minivan loves to make....it will "groan" (literally) when you have it too the floor trying to get up to about 110mph, it can do it.....but you can almost watch the tank needle fall, and the groaning noises aren't very comforting Its got a 3.0 litre V6....rated at like 168 hp or something.....above 45-55 the torque is gone. Just rev's to about 6500rpm (quite loud!!) and slowly climbs the needle higher, allll the way to around 105, then thats about it. The diesels have an incredible amount of power even up at 80-85, its awesome. Yes they are louder than the van, but far smoother/powerful feeling.

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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)