I find that the last .6 gallon is unusable.
So if I run until it takes 3.9 gallons to fill up I am sputtering to the gas station.
I always fill up when I need 3 gallons to fill up. And that is typically at about 130 miles.
Yep I have the factory service manual.
Maybe they will give you free roadside service. My MB has that feature where they will bring me 3 gallons of gas free or help jump start the car or replace the battery.
If I don't use 4.5 gallons though, I will not know how much it holds. That would waste the running out of gas. Also there was another thread on this a while back, but I did not see a conclusion to the question.
Last edited by sco0842; 17th July 2012 at 03:45..
Reason: added thought