What gauge is the most accurate indicator of running out of gas? The fuel gauge, the Estimate to empty, or the fuel used? My initial guess would be the fuel used assuming that the injectors know exact how much they metered in. I'm really just curious because the gas gauge and the estimate to empty, seem to indicate that i'm lower on fuel then the fuel used gauge.

 

The "fuel used" gauge is nearly always about 1-gal off whenever I fill up. It always says I used less fuel than I actually did. Which in turn throws the MPG gauge off as well.

 

I found on my 13 if I compare the pump gallons to the fuel used when the pump clicks off the first time, that they are very close. If I add more, they are different.

 

My fuel used is pretty close in warm weather, farther off in cold weather. I've come to the conclusion that the fuel used calculation is based off the table that is used once the engine is at operating temperature but until it reaches operating temperature it runs rich and thus uses more fuel.

In my last F150, the DTE was not a great indicator, I think it calculates with a reserve). Fuel gauge does the same. And if gallons used is off, it usually reads low.

Based on those three things, the last thing I would use is gallons used if I planned on stretching a tank because since it tends toward the low side, you'd have a higher change of running out of fuel.

 

That's exactly what I do. I never put more in after it clicks off.

 

Use all the tools available, distance to empty is very conservative based on your normal driving style, I never let the tank get below 1/4 if I can help it...
I did have an issue where I was running low and was on a long distance trip and wanted to see the difference DTE showed I would run out of fuel 50 miles before getting home on a 350 mile trip, I drove with a very light foot and by the time there was 200 miles to go, the DTE displayed 200 miles. The DTE was, for the most part, ticking down 2 miles for every 3 miles I drove, so i think it was measuring out what was going through the injectors while keeping the estimate based upon my average driving style.

 

Where is the "Fuel Used" indicator ???

 

Exactly what I was thinking. My last truck had it but haven't seen it on this
one. It made me go out and look for, I can't find it.

Maybe they didn't put it on the 16's.

 

I'd say the gauge is most accurate. My gallons used is always about 1 less than I fill. Sometimes 1/2, sometimes 2.

 

Here in Ontario Canada, fuel at the pumps is volume corrected to 15*C. I only checked once on a trip after a fill up, and like one other mentioned it was off about 1 gallon (4 liters in my case ) When the pump clicks off the first time, It is hard for me to get another liter in and the time i was checking, I stopped at the first click off.
So is it a volume corrected thing?