16 gallons in a 20 gallon ?

New here, new to Jeep's, and I searched a bit before posting this:

DTE reads 7 miles, stop to fill up the tank, and about 16 gallons goes in. This is consistently the experience. No other fuel gauge problems that I can tell.

The build sheet on the vehicle states a 20 gallon tank, as does Edmunds specs and the like, so it seems obviously off.

Is there a fuel capacity, DTE reading, of fuel gauge reset function to correct this or do I have another part to replace?

Thanks!

On my XJ with a 20 gal tank I have around 2-3 gallons of gas left when the light stays on constantly. When the light first goes on and then goes off and on for a while as you make turns and drive around it would be safe to say you have around 4 gallons left. My XJ doesn't have the DTE display on it but my ZJ does and when my light goes on it displays anywhere from 50-70 miles of driving left so if yours is reading 7 miles left something is definitely off with the reading but I'm not sure what you would need to fix.

Possible that your tank has a big dent in it also to the point where there is fuel "blocked off" from the reader float so it doesn't know it is there and it reads empty.

Cottontail said:

Possible that your tank has a big dent in it

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Not seeing any dent.

thanasi85 said:

if yours is reading 7 miles left something is definitely off with the reading but I'm not sure what you would need to fix.

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I'll get it to 0 DTE and beyond, carry a 5 gallon can, and see how much it's off by. When it claims empty, I'm thinking that it's got +/- 4 gal. left; like you're thinking.

I've run my 2000 XJ to the point where I dumped 20.9 gals at a fuel stop and it was still running.
The DTE is an estimate, based on several variables but are rarely calibrated to an exact empty, so folks don't get left stranded 50 miles from a fuel station.

If your really want to know how far you can push your rig when the DTE light comes on, until empty, try this:

The next time your low fuel light comes on, note the actual mileage on your odometer and then throw a gas can containing 3 gals in the back of your rig and continue driving until you're out of fuel.

Note the difference in miles from when the light came on and the rig shuts down. Dump the fuel from the can into the tank and head to the nearest fuel station and note the amount of fuel added to bring it to full.

Agreed. My wife's got a Caravan with the same DTE etc. display and we've run it well beyond 0 before.

The plan is as you stated: have a can and drive it till it needs what's in the can, making not of the odometer, and what gas is needed to top it off after that.

Try having what you thought was a 21 gal tank, cause when it read empty, you put 18 or so gal in it and it said full, and the 21 gal tank was stock that year (79 dodge ramcharger, not jeep).

Fast forward to the time the fuel gage stops working. No biggie, drive by the lousy mpg you get.

Ok, while on a road trip, you get to talking to someone and just kinda forget you are supposed to stop and get gas when you've gone 200 miles (20 gals x 10 mpg). Realize this when you are at 300 miles driven. Freak out, and pull off at the next exit for gas.

Fill up, and promptly put 33 gals in the tank. Hmmmm.......get all the station info in case they are ripping you off, cuz the flunky working there is clueless.

Get home, and it turns out, my truck had a 35 gal tank in it from the factory, but they put a 21 gal tank fuel sending unit in it.

How's that for crazy ?? Would have probably never known had I not got to talking and drove too far.

I remember I got a good 30 miles after my light turned on, and still had a bit left since I made it to the pump. Also, I always carry 5 gal of fuel in a metal canister. The reason I don't like to go under 1/2 tank though is due to fuel pump cooling

I've run it down to 0 DTE, and then drove another 10 miles offroad and it was only down to about 18 gallons.

I never had an XJ with an actual readout, but on both the 95 and the 99 the light would come on at almost exactly four gallons left. It was very predictable. I'd carry a can and find out for sure. You only have to do it once.