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New 05 LS430 owner here trying to find the real answer to the actual capacity of my 2005 Lexus LS 430 fuel tank.
There are lots of postings trying to address this question but no “real” answer that I could find.
Here is what I did: I drove my car as I normally do until the low fuel light came on. The trip odometer reading was 369 miles.
I had planned for this and had a half gallon of gas in the the trunk to use for the experiment. I would then drive the neighborhood waiting to run out of fuel by the car engine missing.
The car mileage was 418 when that happened at which time I put the half gallon of gas I had in the trunk in the gas tank.
The car started right up and I drove 3 miles to the nearest service station when the odometer reading 421 miles and one half gallon of gas in the tank.
I began filling the car wondering what the final number of gallons would be. 20, 21,22, 23 gallons when the automatic stop fueling stopped. I was then able to add an additional .9 gallons being careful not spill any while adding as much as the car will hold.
So, low fuel light came on at 369 miles. Drove an additional 49 miles when I ran out of gas. Added one half gallon of gas with 418 miles on the odometer. Drove 3 miles to the gas station. Put 23.9 gallons of gas in the tank plus the .5 gallons
added, for a total fuel tank capacity of 24.4 gallons of gas.
Last edited by 0011; 09-24-20 at 09:28 PM.
Reason: Clarity
Using MPG to estimate tank capacity would not be very reliable. Fuel economy can be impacted by a number of factors, such as, driving in stop-and-go traffic, weather (hot, cold, windy, rainy, etc), hilly roadway, A/C usage, open windows/moonroof, load/weight, speeding, fuel injector condition, fuel type, oil type, tire inflation, alignment, and many more. I was surprised that that you were able to put 23.9 gallons in your tank. According to the Owner's Manual, the tank capacity is 22.2 gallons.
And there is additional capacity in the fuel system beyond what's quoted by Lexus; there's what's considered an unusable portion of the tank that contains some (sometimes included in what the mfgr quotes, but often not included) and the gas in the fuel lines, fuel pump, line up to the filler neck, etc.,
It is quite easy to keep pumping gas into our LS430 gas tanks once the filler hose clicks off. I can confirm this. I was doing this for years and it seemed that the tank had an endless bottom. Unfortunately, due to my stupidity, I have been living with a ruined charcoal canister for years PO440. Don't do it! Once it clicks, stop pumping!!!!. The car holds approximately 22+gallons.
I saturated the charcoal canister in our 1999 Toyota Solara.
Discovered that while the Chevrolet store I was working at
back then could just open up a GM canister and refill it with
a prescribed amount of bulk powder, it was necessary to buy
the complete $350 unit to fix the Toyota.
Take away? Don't overfill the tank!
I have always filled my cars and trucks up to the very top. I have stopped this practice after reading something on here about that. My question is how would I know if the canister has been filled with fuel? I take it a warning will come on at some point. I stopped my old practice about 2 tanks ago.
I have to admit that the first time I ever saw a mpg computer was in a Chevy Cruze rental, and I was fascinated. Because I tracked mpg on paper and spreadsheet since 1991. I stopped due to COVID and my 6 y.o. deleted my phone app and I hadn't backed it up.
Anyway, as far as range goes, the car cannot predict the future. It has no idea, if you're going to be taking it on the highway today, or bumper to bumper in the city. I found that when my car became all city driving? Now I got the dreaded 14 mpg of a V8. Until that time? 19 to my other 2 cars' 22, so not a huge penalty. My commute changed.
What would in fact be useful, but I've never heard of it, is a gallons left display.
I will say this--one of our cars has no mpg computer, the other 3 do. The BMW is spot on to the tenth for mpg. The Lexus is within .5. The GM is totally off. This must have to do with the way the cars compute fuel consumed (how is this measured there's no veeder root on the fuel line lol). Because it knows distance traveled.
I've started pumping my own gas again this year. From 2010-2019, got it in NJ full serve at work due to price.
The difficulty with a "Gallons Remaining" display is that it would need to be calibrated for each vehicle as each gas tank varies due to the manufacturing processes.
When they say it has a capacity of 22.2US gallons, what they actually mean is that is has a capacity of AT LEAST 22.2 US gallons.
That is why the fuel gauge is not marked with any actual values.
If you really need range, then buy an S320CDI. They will do an honest 800+ miles per tankful (23.2 US gallons) of diesel but you also get nasty turbo-lag and atrocious reliability.
Personally, I drive until I see the Range get to 50 miles remaining (or the low fuel light shows) and then find a gas station.
If yer going somewhere where gas stations are sparse, that's what jerry-cans were invented for :-)
I really don't see how anyone can consider the 430 to be bad on fuel, drive a modern turbo car to the same level and it will be worse. It's the best car I've ever had for mpg by a factor of 2x and it's great how long it can go without needing to refuel
The difficulty with a "Gallons Remaining" display is that it would need to be calibrated for each vehicle as each gas tank varies due to the manufacturing processes.
When they say it has a capacity of 22.2US gallons, what they actually mean is that is has a capacity of AT LEAST 22.2 US gallons.
That is why the fuel gauge is not marked with any actual values.
If you really need range, then buy an S320CDI. They will do an honest 800+ miles per tankful (23.2 US gallons) of diesel but you also get nasty turbo-lag and atrocious reliability.
Personally, I drive until I see the Range get to 50 miles remaining (or the low fuel light shows) and then find a gas station.
If yer going somewhere where gas stations are sparse, that's what jerry-cans were invented for :-)
It's like the term, idiot light, right? Why display anything at all, if the number isn't accurate. The needle should be accurate, going from F, to E, and our brains are wired to relate to an analog needle decreasing proportionally. And systems seem to be designed to alarm, like an amber or red light when there may be 2 gal left.
No lie, on the E9x BMW--the earlier ones had the oil temp gauge 2/3 the way to the hot end. People complained, so BMW made it so ordinary oil temp is in the middle. I kinda felt that's why there are little tiny numbers by every so many marks, who cares if it's 2/3 towards hot? the LS430 coolant temp is not in the middle, it's a little below. Why doesn't toyota update it so it's smack dab in the middle!
It's like the term, idiot light, right? Why display anything at all, if the number isn't accurate. The needle should be accurate, going from F, to E, and our brains are wired to relate to an analog needle decreasing proportionally. And systems seem to be designed to alarm, like an amber or red light when there may be 2 gal left.
No lie, on the E9x BMW--the earlier ones had the oil temp gauge 2/3 the way to the hot end. People complained, so BMW made it so ordinary oil temp is in the middle. I kinda felt that's why there are little tiny numbers by every so many marks, who cares if it's 2/3 towards hot? the LS430 coolant temp is not in the middle, it's a little below. Why doesn't toyota update it so it's smack dab in the middle!
The fuel gauge isn't calibrated but it is "repeatable" so if the low fuel light comes on at 1mm above the E mark this time, then it will almost certainly do the same next time.
Don't forget that gas tanks are not a consistent shape either so measuring the gas level in the tank does not equate directly to the volume of gas remaining.
I've only once been worried I'd run dry in the LS, but I made it to a gas station before I did. She took 82 liters, so I still had 2 liters left (10 miles) in theory.
I'd like a yellow warning light when I have 50 miles remaining range (which it already does), a red light when 30 miles remaining and a flashing red light when 15 miles remaining.
The yellow warning light on my old Z1300 (fuel-injected) Kawasaki was so bright and irritating that I once covered it with tape because it was lighting up the water drops on my visor and obstructing visibility.
The very next day I ran out of gas and had to push the 750lb thing 2 miles.
I removed the tape and eventually found a lower wattage bulb for the light.
As for the temp gauge, people prefer to think their car is running cooler than others, hence the "slightly below half" <LOL>
All water cooled engines operate between 195F and 220F but some people panic if they see their temp gauge moving up.
My LS temp gauge stays slightly below center pretty much regardless of what I do.
The only time I've seen it rise slightly above mid-way was when stuck in traffic on a 97F day (rare here in the UK).
It moved up and down ever so slightly with the air-con compressor switching on and off.
The fuel gauge isn't calibrated but it is "repeatable" so if the low fuel light comes on at 1mm above the E mark this time, then it will almost certainly do the same next time.
Don't forget that gas tanks are not a consistent shape either so measuring the gas level in the tank does not equate directly to the volume of gas remaining.
I've only once been worried I'd run dry in the LS, but I made it to a gas station before I did. She took 82 liters, so I still had 2 liters left (10 miles) in theory.
I'd like a yellow warning light when I have 50 miles remaining range (which it already does), a red light when 30 miles remaining and a flashing red light when 15 miles remaining.
The yellow warning light on my old Z1300 (fuel-injected) Kawasaki was so bright and irritating that I once covered it with tape because it was lighting up the water drops on my visor and obstructing visibility.
The very next day I ran out of gas and had to push the 750lb thing 2 miles.
I removed the tape and eventually found a lower wattage bulb for the light.
As for the temp gauge, people prefer to think their car is running cooler than others, hence the "slightly below half" <LOL>
All water cooled engines operate between 195F and 220F but some people panic if they see their temp gauge moving up.
My LS temp gauge stays slightly below center pretty much regardless of what I do.
The only time I've seen it rise slightly above mid-way was when stuck in traffic on a 97F day (rare here in the UK).
It moved up and down ever so slightly with the air-con compressor switching on and off.
I was also going to say, our fuel capacity is fixed, it doesn't vary from car to car, right?
Interesting how brains work....probably why it doesn't bother too many people (I am bothered) that a half gallon of orange juice is now 52 oz. I feel like 12 oz is missing.
The 81 oz. gallon of bleach really takes the cake, and bleach is expensive today, where's the other 47 oz?
The BMW oil temp gauge was crazy at least to me, engine runs at the identical temp, now the needle is in the middle, because the scale changed and went much higher (the much higher is not useful, if your engine ever got that hot, there's a real problem, I mean it's like having a volt meter go up to 22 volts or something). But as a car company BMW was like that 15 years ago, took their audience very seriously. Before my time, they retrofitted steering racks to anyone who wanted it circa 2000-2001 because buyers felt it didn't have the tightest of feel compared to the previous generation. What they did refuse with my model, is folks with auto trans randomly got external oil coolers, whereas the manuals all got them with ZSP. They refused to retrofit those to auto owners who lacked them....
I was also going to say, our fuel capacity is fixed, it doesn't vary from car to car, right?
Interesting how brains work....probably why it doesn't bother too many people (I am bothered) that a half gallon of orange juice is now 52 oz. I feel like 12 oz is missing.
The 81 oz. gallon of bleach really takes the cake, and bleach is expensive today, where's the other 47 oz?
The BMW oil temp gauge was crazy at least to me, engine runs at the identical temp, now the needle is in the middle, because the scale changed and went much higher (the much higher is not useful, if your engine ever got that hot, there's a real problem, I mean it's like having a volt meter go up to 22 volts or something). But as a car company BMW was like that 15 years ago, took their audience very seriously. Before my time, they retrofitted steering racks to anyone who wanted it circa 2000-2001 because buyers felt it didn't have the tightest of feel compared to the previous generation. What they did refuse with my model, is folks with auto trans randomly got external oil coolers, whereas the manuals all got them with ZSP. They refused to retrofit those to auto owners who lacked them....
Oh it varies quite substantially from car to car. The gas tank is made from stamped steel pieces that are welded together.
Additionally the shape is quite complex and chances are that manufacturing variations will lead to significant capacity changes.
It's not something that they need to be ultra precise on so long as it always exceeds the stated capacity.
Then there is the effect of temperature. If you fill up in temps of -10F the tank will take less gas than at 110F.
Why you only get 81 fl oz in a "1 gallon" container of bleach I have no idea.
Is the container marked or sold as 1 gallon? If not, then it's not a gallon :-)
I can't comment on BMWs as I don't fit in them, no not even in the 7-Series.
Oh it varies quite substantially from car to car. The gas tank is made from stamped steel pieces that are welded together.
Additionally the shape is quite complex and chances are that manufacturing variations will lead to significant capacity changes.
It's not something that they need to be ultra precise on so long as it always exceeds the stated capacity.
Then there is the effect of temperature. If you fill up in temps of -10F the tank will take less gas than at 110F.
Why you only get 81 fl oz in a "1 gallon" container of bleach I have no idea.
Is the container marked or sold as 1 gallon? If not, then it's not a gallon :-)
I can't comment on BMWs as I don't fit in them, no not even in the 7-Series.
I did not know that! That the capacity had a variance. I'm pretty sure my wife's GM is a composite, it has a rail that's supposed to protect it in the event of an accident.
I always cringed when on the news a county team would go out and find that pumps didn't really dispense 1 gal, or that the octane for premium was not that. It seems not that difficult for a retailer to get away with. And if they see the county come out with testing equipment? Magically the gas station experiences a power outage. It's insane! but funny too when it's on TV