Fuel/water separator filter turning black

[schISM]

(09-06-2020 )Waterloo Wrote:  Mine stays clean, but I am picky about where I purchase fuel. Only straight diesel, no bio or whatever else outfits like Flying J and Pilot pollute their fuel with. I primarily purchase from TA and Petro.

Careful, here in Illinois by law they do have to label the pumps with a B-5 through B-20 sticker but some stations get creative as to where they put that label. I know B-11% goes to the Morris TA on I80 and the TA at the Hampshire exit off 90. Not sure if either have straight #2 pumps like Petro does.