I've only used a little of the stuff. On my way to BTS last Nov in Southern IL stopped at a BP station and sticker on pump said it was 5-8% bio. There was no straight diesel offered but price was same. Smelled a bit different, didn't notice and power/mileage changes.
Second time earlier in the year I was up north of Boston and found a place selling B20 again same price as reg diesel. This time I did notice a bit better mileage and an overall smoother engine at the slight expense of some power.
I made my fuel system B100 compatible and would run the stuff all the time but no one nearby (within 30 min drive) sells it.
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the
1997 F-350 XLT 7.3L PSD 4x4 CC LB BTS E40D Manual Hubs 4.10 36000 miles when purchased 4/1/06. Mods - ISSPRO Performax gauges, Tymar intake, Tymar 3x4 DP to 4" ss exhaust, electric fuel, CCV mod, tru-cool 4739, Swamps 175/30% injectors, stage I Stealth pump, D66 turbo
Spearco 6.0 cac, BDP live tuned tuned 442hp/860tq.