Couldn't find my real answer, though at a quarter tank is probably the closes. For the frequently local driving that I do, I simply integrate gas purchases with planned travel based upon minimizing per gallon expense by avoiding extra driving to buy gas or paying a higher price than at my preferred station.
When in less familiar territory, I do my best to do the same and the cruising range of the TCH and Garmin NAV Fuel options help immensely.
Don't want to hijack the thread, but this and the TCH 700 mile tank thread leave me with a non-engineer's nagging question. Doesn't actually running out of fuel always pose a risk of system damage to any modern ICE vehicle?
I let this assumption guide my planning.
Perhaps I'm scarred or brain damaged from the my teen driving years..... (Gas at 29-36 cents per gallon). I really never developed a taste for leaded gasoline through a siphon hose and have yet to taste unleaded or ethanol based products.
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