Actually I've still been filling up when my usage changes (trips vrs local) so that I can show the difference in FE between types of driving so I have some fairly low volume fillups in my history records.

However, I do appreciate knowing what the limits are for that once in a lifetime (like last week for me) situation where I'm on "0" and no gas station in sight. If you know you have another 50 to 75 miles after empty then there is no reason to fill up at the 1/4 mark unless you have specific reasons to do so. I don't need to run the test and I don't really see why anyone else needs to continue doing it. It would have been nice if Toyota had simply said there was a 2 gallon reserve.

I may be old school. First of all, I use 1/4 mark to make a mental note of "OK, I need to get gas soon". I hate to be in a situation where I have to get gas now. There may be a number of stations around, but I'd rather not pay a premium at an expensive station because I need it now. Also, I've always understood that it's easier to get condensation in the fuel tank (not a good thing) the emptier the tank is. Although it's a good bet that the fuel reading is conservative, what if yours is not. For your first tank why not fill up when the gauge is stating 100 miles left. If you still have 6 gallons then you know it's conservative.

The gauge may read 13 miles until empty and you may still have two gallons left. But you don't know that on your first tank. Maybe at 50 miles showing you have 1/4 gallon left. Why take a change stranding yourself and possibly doing harm to the engine and hybrid system. If someone wants to run down until fumes that's their business. I won't do it because of potential condensation problems, especially in cold weather. But on the first tank of gas when you don't know how the gauge is calibrated it just doesn't make much sense to me.

I believe the reason why running the car after you are out of fuel is a very bad idea is the way the HV Battery is maintained. Anybody that has any device with a rechargable battery knows that after it has been charged and discharged a few hundred times over 2 or 3 years that the battery's ability to hold a charge starts to diminish substantially. HSD avoids this problem and makes the HV battery last the life of the car (hopefully) by never fully charging or discharging the battery. It is always maintained at a semi-charged state: use it a bit - charge it a bit to avoid the wear and tear of full charge-discharge cycles. I suspect running your car without fuel for more than just a few minutes will shorten your battery life. Worse, the problem will likely show up in the future AFTER the warranty. It might be cheaper to call for a tow than run your HV battery down.

The key to me here (after reading everything I can find on this point here and elsewhere) is that the car *has a 2.5 gallon reserve.* Every other car I've ever had has some reserve. I've always made a point of finding a station as soon as it hits the reserve. For the TCH it is different. It has a "hidden" reserve. The light comes on *before* the reserve is hit, and the tank hits empty *before* the reserve. Most cars have a red zone on the gague (the "reserve zone") and also don't turn on a light until you are at or very near the reserve.

Knowing that I have 2.5 gallons *after* dead empty will cause me to treat *empty* as the beginning of the reserve--I can't think of a reason not to. (Afterally, even in bad conditions, 2.5 gallons is worth 50 miles...)

Thanks for the info folks.

(And on the trip computer, I'm not going to input the first tank at all....)

For your first tank why not fill up when...

I totally agree on the first tank. However now that I'm on my 12th tank I do know that I consistantly have extra gas after the E. I've only been there once and not tottally by choice. I did decide on my trip to Nags head to run my tank further down than normal. However with about 20 miles showing and rolling along the interstate I saw no need to panic, However when the interstate ran into 2 lane on 64 East, I was surprised to see NO gas stations for several miles. When my gage did hit the "0" mark I found a station within 2 miles. It took a little over 14 gallons to fill up.

At this point, if I'm travelling a (really) long distance I see no reason to stop at 1/4 of a tank. Running closer to empty actually gives me a cushion of 50 to 75 miles and is no more risky than filling up at 1/4 tank on a car that is empty when it says it is.

Like I said, this test only needs to be ran once and it has been. I see no need to run my tank to empty in normal circumstances as I want to fill up at my local BP (where I get an additional 5% discount with my BP card. So I may fill up even though I have well over a quarter of a tank just so I know I'm full when I leave and that I know I've gotten my gas at a station of my choice.

In 1982 I purchased a new Toyota Tercel. I decided to see when the 'low fuel' indicator would come on. Guess what. It didn't work. Did I hear 'I told you so' more than a few times.


WVGasGuy,

You pretty much went right by my house on your way to Nags Head. I live about 1 mile east of the Chesapeake Expressway when going through Chesapeake on your way there.

Thanks for all the helpful feedback. Love this community.

Side note: Jeesh, some of you run out of gas frequently. I've been driving all sorts of cars--from clunkers to new luxury--for 20 years and I've never run out of gas once.

I do think it's important to know what your fuel gauge is telling you and I'm glad someone has verified this.

In a past Lincoln MarK VII that I purchased used I ran out of gas on the interstate before it hit the empty mark. There are times you'll catch yourself low and it's good to know if you can make it home or to the next exit.