Fuel Gauge and Tank size

[Mmmauldin]

I’m on a roll this week. Gas went up to 4.05 here in south Mississippi. We had just over 3/4th a tank left so I was expecting 4-5 gallons to fill up. Nope. 10.2 galleon to fill up 1/4th a tank according to the fuel gauge. Has anyone else tested this out to see what the fuel Amt was?

23 gallon tank / 4 = 5.75 gallons. Not 10.2.

 

[RichSNJ]

I don't know why, but most cars seem to do this, the gas tank gauge moves slower at the top end of the tank than the bottom. Maybe it has to do with the physical shape of the tank? I drove 200+ miles today and it's still showing above half a tank, I don't think I'll get another 200 out of it.

 

[GCOverland]

See here:

Fuel Gauge

 

[GCOverland]

I don't know why, but most cars seem to do this, the gas tank gauge moves slower at the top end of the tank than the bottom. Maybe it has to do with the physical shape of the tank? I drove 200+ miles today and it's still showing above half a tank, I don't think I'll get another 200 out of it.

Oh, the Jeep is even more special: The gauge can actually go UP while the engine is running! Again, I'm referring to the gauge and not just the range which would be normal.

 

[eleceng1979]

Only the L can idle and create more range and increase fuel levels… its a jeep thing only reserved for the L, hence why it’s so special. The hybrids and electric are so jealous.

I’m thinking the fuel tank is a really funky shape or the software calibration is really horrible. Maybe they did away with a level gauge and use distance from top/measuring air gap now?

Your math is wrong… you forgot to add the customer dissatisfaction ratio to your equation…

23 gallon tank / 4 = 5.75 gallons / 53.67% dissatisfaction = 10.2 gallons

 

[jeepgrady]

Supposedly the L has a saddlebag shaped tank hanging over the drive shaft.

 

[RichSNJ]

Supposedly the L has a saddlebag shaped tank hanging over the drive shaft.

That would do it.... Maybe even explains the levels going up if the sender unit is on one side and fuel slops over...

 

[dseffren]

I think the best practice is always to keep a half a tank in the car. It goes back to my days of my 1986 CJ7 in high school where the gas gauge was as accurate as today's Mainstream media. My 2021 Jeep Grand Cherokee Overland is a 3.6L and we get 22-25 on the highway, just took a trip to ski in West Virginia and still averages almost 21 going through the mountains. I didn't order the Hemi expecting similar mileage, and yes, the timing isn't ideal with gas prices going through the roof, but that is temporary. Fortunately, I don't pay for my gas, so I just have to worry about the '21 Grand Cherokee (WK2) my '21 Wrangler and the '21 Passport.