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Have had the JK for about two months. I get the fuel down to about 40 miles left to empty. If I have a 22.5 gallon capacity, why can I get only 16.5 gallons in?
 

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It is pessimistic, for starters. It will tell you there is no more before there really is no more.
Also, if you have a JK and not a JKU I am not sure you have a 22.5 gallon tank. I thought the bigger tank was only the JKU. The JK should be just over 18 gallons.
 

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Have had the JK for about two months. I get the fuel down to about 40 miles left to empty. If I have a 22.5 gallon capacity, why can I get only 16.5 gallons in?


I have a jku and when I fill up I can get about 18gallons. The fuel tank will hold a reserve unless you run it empty and it dies. I have also replaced the tank in mine and when my trail dash says 10% or so I still have about 4 gallons left.


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The distance to empty is just a rough approximation. There's no way the trip computer can know exactly how many miles you have remaining. (Even your MPG readout is a rough approximation -- If you hand calculate your miles/gallons after a fill, you'll see it's not exact.).

The distance to empty reading can't take account variations in driving conditions. Consider you're traveling on a level highway. You turn right and the road goes up a steep grade for 50 miles. In this case you will get less than 40 miles.. Now if you were to turn left and go down the steep grade for 50 miles. You'll get more than 40 miles going downhill.

Also consider that the fuel pickup can't drain the tank until it's bone dry. There will be a half gallon or so sloshing around when the engine dies from lack of fuel.

Don't depend on the range indicator when you're getting down to fumes in the tank...
 

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The gauge is not super accurate. Mine is JK and I just use it as reference. On my Jk the furthest I have driven is 270miles. and refueled 15.4 gallons, so i would said I still had 2.5 usable left on the tank.

On a curious note, my headunit gets readings from the OBDii port and the fuel as much as i fill it all the way to the top, it will never read 100% it tops at 96% may guess is that some how the system is calibrated to warn you a little bit ahead of time, as a safe precaution.
 

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The distance to empty reading can't take account variations in driving conditions. Consider you're traveling on a level highway. You turn right and the road goes up a steep grade for 50 miles. In this case you will get less than 40 miles.. Now if you were to turn left and go down the steep grade for 50 miles. You'll get more than 40 miles going downhill.
A 50 mile steep grade? Where are you driving, Olympus Mons on Mars? :bop:
 

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I agree and also have this issue. I have a 16 JKU and when I am on E I still have like 3.5 to 4 gallons left. Not annoying until winter when the Auto Start will shut down if the low fuel indicator is active (something about running it dry). I guess its much better than having a 1/4 tank on the gauge with zero gallons in the tank.

Must be a Chrysler thing because we own a few different Chrysler products and they all have the same inaccuracies on the fuel gauge.
 

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JFI only The fuel pump is in the tank, the pump is submerged and cooled by surrounding fuel, I rely don't Know if it is fact or fiction that running the tank near empty can over heat the pump and shorten its life. If this is true why gamble, when mine gets down to 1/4 I fill it up.
 

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The distance to empty reading can't take account variations in driving conditions. Consider you're traveling on a level highway. You turn right and the road goes up a steep grade for 50 miles. In this case you will get less than 40 miles.. Now if you were to turn left and go down the steep grade for 50 miles. You'll get more than 40 miles going downhill.

LOL!
That reminds me of the chevy uplander I once had. Park it on a downward incline with less than a 1/4 tank and you would effectively run out of gas if you idle for more than 10 minutes or so in that position.
 

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JFI only The fuel pump is in the tank, the pump is submerged and cooled by surrounding fuel, I rely don't Know if it is fact or fiction that running the tank near empty can over heat the pump and shorten its life. If this is true why gamble, when mine gets down to 1/4 I fill it up.
100% true the pump uses fuel as lubricant and coolant agent. If you run it dry I could overheat and shorter the life of the pump.
 

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100% true the pump uses fuel as lubricant and coolant agent. If you run it dry I could overheat and shorter the life of the pump.
The JK fuel pump has a built-in reservoir that is constantly full until it is literally bone dry, at which point your pump isn't going to be running anyway. Filling at 1/4 full is just wasting range.

For applications without a reservoir, modern fuel pumps aren't nearly as sensitive to this as people seem to think. Pumps are also cooled by the fuel flowing through them, after all, which is why higher-flowing external pumps aren't a problem.
 
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JFI only The fuel pump is in the tank, the pump is submerged and cooled by surrounding fuel, I rely don't Know if it is fact or fiction that running the tank near empty can over heat the pump and shorten its life. If this is true why gamble, when mine gets down to 1/4 I fill it up.
That might have been true long ago but I don't think it matters anymore. I had a 2007 Chrysler that I owned for 11 years and I consistently ran it down to when the low fuel light would come on plus some. I never had a problem with the fuel pump.

Filling it up when there is still 1/4 tank of fuel left just means more trips to the gas station but I guess people can go in the store and get their Big Gulp drinks while they're waiting.
 

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The only time I was really worried about running out was in my 2015 Sahara. On a trip to NE Georgia, I let it get lower than I normally do and the DTE readout went from miles to "Low Fuel". When it did that I was about 20 miles from town. I stopped at the first station and managed to put about 17.5 gallons in.

I stopped at the first gas station in town (a good 20 miles from the camp) and managed to squeeze 17.5 gallons into the tank. Normally I fill with the gauge at about 1/4 full or just a little less and manage to put 15 or 16 gallons in.
 

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I sure didn't know the JKU tank was that size. I usually run mine until it says about 40-50 miles to go and it usually takes around 16-18 gallons to fill it up. I always assumed it was about an 18 gallon tank.
 

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I'm also not convinced you can fill the tank completely. When I fill up my JKU, the TrailDash readout says 95-96%. I don't think I've ever seen it at 100%.


I have gotten more than 20 gallons in the tank though. I was coasting into the station on fumes that night.
 

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I'm also not convinced you can fill the tank completely. When I fill up my JKU, the TrailDash readout says 95-96%. I don't think I've ever seen it at 100%.


I have gotten more than 20 gallons in the tank though. I was coasting into the station on fumes that night.
Were you REALLY?
Way back when I was driving a van pulling a trailer full of racebikes and stuff heading out I-68 late at night. I have a habit of pushing the full range. It is fairly desolate out that way on I-68 in WV. After trying to hit a gas station that isn't there any more I finally got to an exit with a actual gas station. The van died as I headed down the exit ramp. I coasted down the ramp and into the gas station, luckily it was a fairly straight shot. It was hard to turn all that weight with no power steering. We mentioned the failed attempt at the previous gas station (we could not find it despite the sign saying it was there). The old man said "Heck, they closed down that gas station yeeeaaarrrrs ago". That is my best low gas story that didn't end with me stuck on the side of the road.
 

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I'm also not convinced you can fill the tank completely. When I fill up my JKU, the TrailDash readout says 95-96%. I don't think I've ever seen it at 100%.


I have gotten more than 20 gallons in the tank though. I was coasting into the station on fumes that night.
Physically you do fill it up to capacity, it just the gauge is designed to read a little lower than capacity to give you an early warning or to account for just a gallon of unusable fuel because is at the bottom of the tank and the pump cant just reach it .

Mine 2 door is the same if i fill it up to the top i get 96% capacity, that translate to 17.7 gallons, exactly 1 gallon less than the advertised capacity.
 
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