Fuel Gage

[scooter6]

I just got a 2020 2500 6.4 and the specs says it has a 31 gallon tank ,so today I wanted to see how many gallons it took to fill it up. The low fuel light came on and said that I had 50 miles range yet so I drove it till the gage read almost empty and the DIC said I had 18 miles left in the tank.I filled it up and it took 27 gallons, I thought it would take more than that like 28-29 gallons. I was wondering if it’s the same with others on this forum with the same truck. BTW I normally don’t ran my tank that low but wanted to see if I had a little cushion or not if I get stuck out in the sticks somewhere and need to get to a station. Thank you

 

[GTyankee]

It is what it is
Everything is working as designed,
The fuel pump needs gas around it to keep it cool
Do Not Top Off the tank, because there is always a chance that when the tank has too much fuel in it, it will overflow & run into the Charcoal Canister & then you will definitely have issues

 

[Wadejesu]

Did gauge read all the way full when filled, My 2020 sometimes does and sometimes not?

 

[dragstrip69]

I think it's typical on most, extra conservative by the manufacturer.

So far on my Ram the low fuel light has not come on but I've been able to put 27.5 gallons in a 33 gallon tank just below quarter tank and 130 DTE, which is very close at my current mpg's of 21.5.

My Tundra's 38 gallon tank low fuel light would come on with 10 + gallons still in the tank, always took 27 gallons right after the light came on.

So at least my Ram will go down to at least 5 gallons before the light comes on which is much better than the Tundra.

I mostly fill up at a quarter tank and it takes 25 +/- gallons after 525 +/- miles.

 

[scooter6]

After fill up the gauge goes to full but comes off full after 10 miles. My 1500 which I traded in ,fuel gage was pretty much spot on, maybe I just got spoiled. Thank you

 

[SniperDroid]

Same 31 gallon tank, Low Fuel warning comes on at about 7 gallons left in the tank. The owners manual states is should come on at about 3.3 gallons left. I have some other issues to take it to the dealer for, so I'll add that to the list. I'll let you know if they blow me off or not....

 

[GeometryFletch]

When it says 50 miles left that's an estimate based on the mpg you're getting at that time...It's a 31 gallon. If you really want to verify run it til you run out of gas then fill it up

 

[Gondul]

Funny... I intentionally ran it out of gas
=================
Ran the truck until the "LOW" indicator showed up on the DTE Dial.
Drove another 40-ish miles before I ran out of gas... there was no sputtering or warning, it simple stopped running.
Waited 30 seconds or so and then hit the 'Start' button again... all it did was crank and did not fire up.

I put in 5 gallons out of the can I brought with me for this purpose and the truck started right up.
It was then a 2 mile drive to the gas station where I added 25.88 gallons of gas.

I added a total of 30.88 gallons of gas *after* running it dry....pretty close to 31 if you ask me.

So 410-ish miles at 13-ish mpgs is when I ran out of gas.
Mostly home to work mileage (30 miles round trip surface/highway is 50/50)

 

[GTyankee]

You may not like it, but the tank will have approximately 5 gallons in it when empty & if you run it until the engine stops, there is still a couple of gallons of fuel in the tank.

As far as the fuel gauge goes, the miles until empty is speed related.
If your doing 80 mph & your light comes on saying that you can go another 50 miles, you can slow your speed to say 50 & don't be surprised if your light goes off

 

[SniperDroid]

Went to the dealer last week with some issues, Fuel Gage among them... purposely left the tank below one quarter when I took it in, figuring they may want to drain it to check something. When I picked up the truck, the service writer told me the tech scanned the code on the tank and it's definitely a 31 gallon thank. The computer showed 17 percent fuel in the tank and the Gage read the same. They found nothing wrong. I used TORQUE to check the fuel level yesterday, and it read 6 percent. Did some driving down to 4.5 percent. That should have been a little over a gallon left in the tank. Went to my usual Top Tier gas station to fill up.... the most I could squeeze into the tank was 26.4 gallons. Maybe it's designed with a bubble in it that never fills, or the intake port for pump is too high, or only some engineer in an office is having some sport with us... but these tanks won't hold 31 gallons of fuel.

 

[Gondul]

Went to the dealer last week with some issues, Fuel Gage among them... purposely left the tank below one quarter when I took it in, figuring they may want to drain it to check something. When I picked up the truck, the service writer told me the tech scanned the code on the tank and it's definitely a 31 gallon thank. The computer showed 17 percent fuel in the tank and the Gage read the same. They found nothing wrong. I used TORQUE to check the fuel level yesterday, and it read 6 percent. Did some driving down to 4.5 percent. That should have been a little over a gallon left in the tank. Went to my usual Top Tier gas station to fill up.... the most I could squeeze into the tank was 26.4 gallons. Maybe it's designed with a bubble in it that never fills, or the intake port for pump is too high, or only some engineer in an office is having some sport with us... but these tanks won't hold 31 gallons of fuel.

I literally put 30.88 gallons of fuel in the truck after running it dry...

 

[SniperDroid]

I literally put 30.88 gallons of fuel in the truck after running it dry...

I guess it just SUCKS to be me....

 

[GTyankee]

The fuel gauge is in the lower part of the fuel tank
The fuel filler tube is in the tallest part of the tank
There may be something built into the inside of the tank that keeps the upper part empty most of time, leaving room for expansion.
They may measure the square inches of the Whole tank to get the gallons that are stated in the owners manuals.
When actually the upper part of the tank never hold fuel.

You can see the hole in the center of this Ram fuel tank, that is where the Fuel gauge & pump fits in
https://www.ebay.com/itm/153814628717

Just a thought .....

 

[SniperDroid]

The fuel gauge is in the lower part of the fuel tank
The fuel filler tube is in the tallest part of the tank
There may be something built into the inside of the tank that keeps the upper part empty most of time, leaving room for expansion.
They may measure the square inches of the Whole tank to get the gallons that are stated in the owners manuals.
When actually the upper part of the tank never hold fuel.

You can see the hole in the center of this Ram fuel tank, that is where the Fuel gauge & pump fits in
https://www.ebay.com/itm/153814628717

Just a thought .....

Yeah, hears a thought.... It just SUCKS to be me.

 

[Riccochet]

it's bad to run a tank dry. The fuel pump relies on gas as a lubricant. You can kill a fuel pump real quick by running it dry.

 

[SniperDroid]

Yeah, I did that in two mini vans back in the 90's. Mechanic said not to let the Dodge go below quarter tank too often. They used the fuel to cool the pumps.