I have a 2013 MDX and noticed that when the auto shut off of the fuel pump cuts off, the tank is not really full.
The fuel gauge is right at the "full" mark, not that extra 1/16" or so beyond it. A few times I kept pumping fuel after the auto cut off but dont want to over do it to avoid spillage.

 

there needs to be some air in the tank for multiple reasons so filling the tank completely is never a good idea, not to mention having it overflow would not be fun

 

I could not believe the amount of "extra" space in my 2008 MDX. Normally, if it were completely empty, it would take just over 20 gallons. One afternoon, I was kind of bored and decided to see just how much gas I could fit in there. I kept seeping gas into the tank from the pump, pausing occasionally for 30 seconds to let things settle, and kept going.

The grand total? 25 GALLONS. Yes, 25. 5 gallons of airspace that I was able to fill. I was dumbfounded.

 

Are you certain it was 25 gallons? It's possible the gas pump isn't very accurate when trickling fuel...

 

I couldn't guarantee the exact volume, but my fuel gauge stayed on full for an incredibly long time. Normally, I could see it go down slightly after as few as 20 miles or so.

 

That does sound approximately right when you factor in the reserve gals? Does anyone know how many gals of fuel is left when the gas light comes on?

 

Fascinating!

 

I simply stop when the pump clicks, the difference in volume is not that much, and every piece of literature I've read advises you to not overfill the tank.

 

Just keep on filling that tank, even after the pump tries to stop you.. there is ALWAYS space for more gas. This way, you can drive without refueling for an additional 25 miles or more.. fill it to the brim.. that's what the extra space is there for.. forget what the automatic shut off system, or the manual, or the feds say!!

 

I'm guessing the gauge is that way on purpose so you'd have to be a complete idiot to run out of gas. My TL went to 0 miles range and clicked at 14 gallons when it's a 17 gallon tank, so the gauge reads low so you fill up more often. The air space is there for a reason, the tank is pressurized and sealed. Overfilling can damage your EVAP system. I still normally put a little more in to try to get to an even gallon or dollar amount if I'm feeling OCD.

 

During hurrican sandy NYC had a shortage of gas i filled my tl 3rd gen with 20.5 gallons