Biodiesel has LESS energy in it than Dino Diesel, which makes it impossible to get better mileage, thats defying the laws of energy.

The highest I have e-v-e-r gotten was on a 250 mile drive at 55mph with gentle acceleration and few stops. I got 30.3mpg. Highest I've ever come since was about 29.2 driving once again, mostly at 55mph and coasting to lights as long as I could. Aside from those times (when I was making an exceptional effort to see what I could eek out of it) I have never broken 25mpg. In fact, I usually see about 23-24.5 in the summer, which is mostly highway. And about 19.5-21 in the winter, mostly city driving.

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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)