Do I really have a 19 gallon gas tank?

InOmaha

InOmaha

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My gas gauge got close to E the other day so I filled up. I was surprised when it stopped filling at 14.2 gallons. I've looked up my vin number using the links I found here and I supposedly have a 19 gallon tank. So now I don't know if someone replaced it at some time or it's just the sending unit telling me it's empty early. This site has so much good info in it. https://fcacommunity.force.com/RAM/s/equipment-listing

I guess I'll drive it to beyond E with a small gas can aboard next time to find out. I'll try to track down a video on the tank mod and see if I can figure anything out from the outside.

Back a couple of decades ago, my 1998 ZJ fuel sending unit was off and you had to fill up at 1/8 tank if you didn't want to end up stranded, then it stopped working and the replacement was the opposite where you had 3-4 gallons of gas when you got to E. So this could be a simple, learning my new car type of thing.
 
No the light didn't come on. It was just down inside the red bar on the gauge so I was expecting more like 18 gallons instead of 14. Since I didn't run it all the way down to E, it could simply be the sending unit or I could run myself out of gas.

I drive on the busiest road in our state to get to work in the mornings, so running out of gas even if I have some with me would be a pain and could be dangerous.
 
I don't think it will ever get to 18gal. Seems like once the light came on I could go about 20 miles to a station,Maybe with a tailwind, and still not more than 15 or so gals.I changed my tank out a couple yrs ago to Genrights safari tank. Yeah if you drive in Omaha it's nuts. My wife commutes there daily.
 
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The tank is empty generally when the needle is to the left of the white letter "E" on the gauge. Really, off the red entirely and just off the white lettering on the gauge. It'll be completely empty at that point so if you run it down that low I'd have a backup plan. The red starts around 1/4 tank so what you say makes sense right, 14.X is almost exactly 25% of 19?
 
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It starts around 1/8 of a tank doesn't it? That's why I was expecting around 18 gallons (I assumed 20 instead of 19). I'll just run it closer to E next time and see what I can get in it. My last car when if light came on I had 5-10 miles to empty and at 1/8 of a tank I had 25-30 miles to go. So I just never let it get below 1/4 tank. When my wife's car gets to E and the light comes on, we can drive another 40 miles. So I know fuel gauges (and other dash gauges) aren't the most accurate. It's part of learning a different car over time.
 
You are making the assumption that your gas gauge reads correctly.

From everyone i ever talked to. They never read correctly. At 1/2 a tank in my jeep i can barely put 6 gallons in it. The most i have ever but in it was 12 gallons not counting when i removed and cleaned it. And then i was able to put 19 gallons in it.

Someone will eventually come up with a better fuel gauge until then. Its just as easy to keep filling it up when it gets low
 
On both of my TJs, the gas light would come on and show it was near empty when there was 5-6 gallons left in the tank. The TJ fuel level sending unit is notoriously inaccurate.
 
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@InOmaha i should have read your profile first..... unless "MAJOR" modifications were done it is not possible to put a "factory" 15gal tj tank in you. If memory serves me correctly. It was only done in 97 possible 98 on base models. If your profile is correct. You have a 06 unlimited. That gas tank is much different than the ones that were made in 15gal. 97-02. Is the break point on usage for a 15 gallon tank
 
The fuel gauge is notoriously inaccurate and it always indicates significantly less fuel in the tank than is really there. I don't worry about filling up until it's down to or even slightly below the line below the red zone. Even then there's always at least a gallon or two remaining in the tank.
 
I intended to do an experiment over the summer... I kept a gas can in the back of the Jeep for an entire tank intending to run it out to determine the total mileage I could get from a tank... I ended up just filling the damn thing up because it was reading empty for so long and I was tired of wondering when it was finally going to run out.

FWIW my fuel gauge goes from full to 3/4 in about 15 miles, then it stays on empty for at least 50. The gauge just sucks.
 
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The gauge is perfect especially on the newer bus systems like this 06. Try this. Take a snapshot of your gauge before you fill up each time. Then record the number of gallons you put in. You will very quickly learn that the gauge has always been telling you exactly how much fuel is in the tank you just were unable to read it.

For all those that say the sending unit is bad or inaccurate post a pic of your gauge and the number of gallons you put in to fill it so we all here can see how far off it is. I think it'll become really obvious really quick how "poor" the sending units are.
 
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qslim said:
I intended to do an experiment over the summer... I kept a gas can in the back of the Jeep for an entire tank intending to run it out to determine the total mileage I could get from a tank... I ended up just filling the damn thing up because it was reading empty for so long and I was tired of wondering when it was finally going to run out.

FWIW my fuel gauge goes from full to 3/4 in about 15 miles, then it stays on empty for at least 50. The gauge just sucks.
Click to expand...

Mine went to 1/4 tank, then back up closer to 1/2 tank, then back down to 1/4 in the same day. That and my previous Jeep ownership makes me not trust the gauge, but 5-6 gallons left on E and 1 gallon on E is a big difference. I'll let it go all the way down to E next time and toss in a 2 gallon gas can just in case.
 
Test and report, I'd like to hear what you find. I've had good luck with my gauge and all the newer ones I've ever seen. I've even replaced my sending unit when I did the pump with no change in the readings. I also put 18 gallons in my tank regularly and 19 more than once without running out on both sending units. These thread do pop up frequently and I don't remember seeing one where somebody ended up replacing anything. As @Jerry Bransford says most of us learn that it's fine to drive into the red, that's the way Jeep designed it.

I just did a 100 mile drive back from Arrowhead on Sunday and watched the needle smoothly travel right into the red. It was toward the left end and I put in 17.5 gallons. I knew with the needle still on red I was fine.
 
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