Range - How Much Gas is "Usable"

So 3.1 gal would be best case at around 20mpg, the slightly over May br factored in based on you "actual" lead foot mpg. Can any more confirm this who are getting say 14.5 mpg. Let's see if the math works. We all want to know about how far we can drive after "empty" shows up on the dash.

If you're towing, a lot less than that.
 
Does the fuel light come on when range = 0, or before? I think these are two different systems. The fuel light comes on when there is about 3.1 gallons of gas left per the manual. Range is a calculation of average? MPG * fuel. I guess both calculations would be based on the fuel volume sensor, but they could go through separate processing in the computer.

To test, I guess someone could see what the range number is when the fuel light comes on.

I know that my Toyota Camry's fuel light comes on well before range = 0, but I haven't thought to check the GX yet.
 
The range number is total shit. I can have a range of 31 miles - go to the gas station and add 6 gallons - they really f'ed this feature up.

That's not that far off - at 14-15 MPG you'd be expected to take on 5 or more gallons when the range shows 31. And there's evidence that the long filler tube enables overfilling (whether that's good or bad is another discussion).
 
That's not that far off - at 14-15 MPG you'd be expected to take on 5 or more gallons when the range shows 31. And there's evidence that the long filler tube enables overfilling (whether that's good or bad is another discussion).
That math does not work though - 5 gallons gets you 75 miles of range - more when on the highway also less in stop and go. If there is logic behind it Lexus used it would be great to know.
 
So far the "likely math formula" I posted still stands for me with an 18.2 mpg average. If someone getting 15 mpg (with stock tire height) cares to post the variables we can check. Need avg MPG posted for a few tanks, range left on meter at fill up, number of gallons to fill (without stuffing), and then range noted directly after fill up. We can plug these into equation and see if it jibes with the 50-60 miles when getting say 15 mpg (which would otherwise only give 45 miles).
 
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I’ve pretty much given up on ‘range remaining’. After towing back and forth to Moab couple weeks ago, local non-towing driving, yesterday a downhill trip from my house to Grand Junction, etc..the indicated range remaining is pretty much useless for me. I’m definitely having better luck just watching the gas gauge itself as it goes down and figuring out based on all of lifelong experience about where I’m at with the gas tank.
If someone figures out how to actually turn off the range remaining number indicator… I would definitely do that. Just my two cents.
 
Came here looking for this thread and was not disappointed. After being confused by my tank size and range, I got in touch with my dealership and just received a really helpful explanation of what is going on with the gas tank that I thought I'd share. I'm not happy with the explanation, but at least now the numbers make sense.

The 21.1 gallon gas tank is the 'dry' measurement of how big the tank is when it comes off the assembly line. But this is not how much "useable" gas the tank can hold. Once full, there are around 1.6 gallons that will always slosh around in the bottom of the tank below the fuel pickup to cool the fuel pump, as I think another owner mentioned above. Additionally, once the tank is filled, there is still another gallon or so of empty/air space at the top to allow for vapor, fuel expansion, etc. So while the overall volume of the tank may be 21.1 gallons, you really only have about 18.5 gallons of fuel you can actually use, and this is how your range is determined.

This tracks with what I have experienced only being able to add 18+ gallons when I fill up an "empty" tank, and my estimated mileage range of 260-270 miles upon fill up. Apparently there was a law change in 2022 that allows manufacturers to list the fuel tank size as the larger (but unusable) dry volume as opposed to the actual volume you'll be able to use once the fuel is actually put in the tank.

I did ask if the aftermarket has any larger fuel tank options and he said not yet, but that the prior versions of the GX and LX did have these, and it's likely only a matter of time if you really want a bigger tank. Which I do.
 
Came here looking for this thread and was not disappointed. After being confused by my tank size and range, I got in touch with my dealership and just received a really helpful explanation of what is going on with the gas tank that I thought I'd share. I'm not happy with the explanation, but at least now the numbers make sense.

The 21.1 gallon gas tank is the 'dry' measurement of how big the tank is when it comes off the assembly line. But this is not how much "useable" gas the tank can hold. Once full, there are around 1.6 gallons that will always slosh around in the bottom of the tank below the fuel pickup to cool the fuel pump, as I think another owner mentioned above. Additionally, once the tank is filled, there is still another gallon or so of empty/air space at the top to allow for vapor, fuel expansion, etc. So while the overall volume of the tank may be 21.1 gallons, you really only have about 18.5 gallons of fuel you can actually use, and this is how your range is determined.

This tracks with what I have experienced only being able to add 18+ gallons when I fill up an "empty" tank, and my estimated mileage range of 260-270 miles upon fill up. Apparently there was a law change in 2022 that allows manufacturers to list the fuel tank size as the larger (but unusable) dry volume as opposed to the actual volume you'll be able to use once the fuel is actually put in the tank.

I did ask if the aftermarket has any larger fuel tank options and he said not yet, but that the prior versions of the GX and LX did have these, and it's likely only a matter of time if you really want a bigger tank. Which I do.
I'm waiting for Long Range America to release the auxiliary tank for the GX which probably won't be out until early 2026. Getting mid 288 miles of range on my best week is annoying.
 
So 3.1 gal would be best case at around 20mpg, the slightly over May br factored in based on you "actual" lead foot mpg. Can any more confirm this who are getting say 14.5 mpg. Let's see if the math works. We all want to know about how far we can drive after "empty" shows up on the dash.
I’ll do it! Stand by for an update.
 
Came here looking for this thread and was not disappointed. After being confused by my tank size and range, I got in touch with my dealership and just received a really helpful explanation of what is going on with the gas tank that I thought I'd share. I'm not happy with the explanation, but at least now the numbers make sense.

The 21.1 gallon gas tank is the 'dry' measurement of how big the tank is when it comes off the assembly line. But this is not how much "useable" gas the tank can hold. Once full, there are around 1.6 gallons that will always slosh around in the bottom of the tank below the fuel pickup to cool the fuel pump, as I think another owner mentioned above. Additionally, once the tank is filled, there is still another gallon or so of empty/air space at the top to allow for vapor, fuel expansion, etc. So while the overall volume of the tank may be 21.1 gallons, you really only have about 18.5 gallons of fuel you can actually use, and this is how your range is determined.

This tracks with what I have experienced only being able to add 18+ gallons when I fill up an "empty" tank, and my estimated mileage range of 260-270 miles upon fill up. Apparently there was a law change in 2022 that allows manufacturers to list the fuel tank size as the larger (but unusable) dry volume as opposed to the actual volume you'll be able to use once the fuel is actually put in the tank.

I did ask if the aftermarket has any larger fuel tank options and he said not yet, but that the prior versions of the GX and LX did have these, and it's likely only a matter of time if you really want a bigger tank. Which I do.
This is a great explanation of our "usable" fuel and how the tank is "built". Makes sense but this is a BIG mistake on the part of Lexus. :(
 

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