I filled the tanks on my Pete with Commercial Bio one day. about 150 gal added to apx 150 gal of ULSD. I had a Cat C-16 and a 13spd Eaton. I noticed an immediate drop in power and fuel mileage (went from 6 down to 4.
also had to change the fuel filter afterwards as it was very restricted! Also, I had an odd craving for french fries the whole time! Never did that again! I have friends that have had major problems after trying bio as well as major problems with ULSD! I have some other friends who haven't had any problems with either (of course they are running newer/lower mileage trucks...)
I have been considering giving bio/homebrew another go, but on a 6.5/6.2 or other smaller/older motor for a pickup or such that wont raise any suspicious eyebrows...
Laterz,
Gator
>|--|~