I just filled up with 2 red bars showing on fuel gauge and saying 55 miles till empty. $43 @ $3.259= 13.19 gallons. Book says 13.2 gallons. Could my sender be off(I don't want to run out) or could this station have ripped me off? Does 13.2 include reserve?

'09 Cooper S

 

Never mind I found this...https://www.northamericanmotoring.co...-capacity.html

 

Usually the manufacture is accurate on tank size, and that's to the full mark.
Then you usually have a 10% vapor space.
So my f60 has a 16.1 gallon tank to full, and I capped it off once since I was on a long freeway run, and put in 1.75 more to just under the fill opening lip.