I doubt they made anything 'verbotten', but companies do certify their engines for different blend levels. In europe most diesel is already a B2 or B5 blend since it is low sulfur and needs something for lubricity.

There are some questions about B100's suitability in common-rail diesel injection systems, and they might just be taking the cautious road. Here in the US warranty issues are a bit vague. I believe there is some legal quandry when it comes to someone using a fuel that isn't 'approved by the manual' but is an ASTM certified alternative fuel..

I'd love to see more info on MB's stance, but I'm not surprised that they'd take a conservative stance right now, even while Jeep Liberty TDIs will be shipping with B5 in the tanks.

peace,
sam

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"That f***in' biodiesel is makin' me hungry."

1982 300TD Astral Silver w/ 250k (BIO BNZ)
2001 Aprilia SR50 Corsa Red w/ 5.5k (>100 MPG)