How much is left when lo fuel light comes on?

[tomseeley]

I'm driving a 2002 GMC Sierra 2500HD duramax crew cab. The manual says my fuel tank has a 26 gallon capacity.

 

Does anyone know pretty accurately--perhaps from first hand experience!--about how much fuel is left when the lo fuel light comes on?

 

I've cut it close a couple times, running maybe 5-10 miles after it came on, before I found a diesel station out in the middle of nowhere, and I've usually put in something like 24 gallons. I'm curious how close I cut it!

[pwall]

Those 'low fuel' lights generally come on when you're done to 1/8 of a tank.

So, for a 26 gallon tank, the light will come on at approximately 3 1/4 gallons left.

 

Of course, there are good reasons not to let your tank run too low (picking up dirt in the bottom, fuel pump heating up, etc).

[tomseeley]

Those 'low fuel' lights generally come on when you're done to 1/8 of a tank.

So, for a 26 gallon tank, the light will come on at approximately 3 1/4 gallons left.

 

Of course, there are good reasons not to let your tank run too low (picking up dirt in the bottom, fuel pump heating up, etc).

 

<{POST_SNAPBACK}>

 

 

 

Thx. I had heard something to the effect of 3 gallons. I appreciate knowing I was close to the truth!

 

And I definitely know I shouldn't let it get that low! But last week, I deliberately skipped an Irving Big Stop along the expressway from Moncton, NB, to Fredericton, because I never imagined there would be NO diesel closer to Fredericton. Well, guess what? I had to backtrack almost 20 miles to downtown Fredericton, towing a 25' trailer, to find fuel, and I coasted in on the fumes! Put in 96 liters! Hence my curiosity!

[pwall]

It's always good to know.

 

The 'low fuel' light became unreliable in my truck about 6 months ago. It's been fixed since.

Stopped in one day to put fuel in as soon as the light came on. On a 118 litre tank, it took 114! That's how I found out the low-level warning was wrong. ;)

[dewfpo]

The 26 gallon tank in these trucks is ridiculous. I often find myself FAR from a gas station and carry a gas can in the bed for insurance.

 

DEWFPO

[DSengineer]

Every truck/sending unit will be different. No general rule of thumb here. Best thing to do is fill it up when the light comes on and subtract from 26 gallons.

 

My prior 99 1500 would come on with about 3.5-4 gallons. My current 2500HD comes on between 2.0-2.5 gallons. I just put a new fuel pump in the 2500HD and have yet to go through a tank of gas. I bet it will read different then the previous however.

[renolaw]

Here in the great state of Nevada, we have 100s of open miles and fuel stops are few an far between. After coming *dangerously* close to running the tank dry and sweating all the way to town, i took some rebar and fab'd up this handy jerry can rack. it mounts to the rear of the tool box and to the floor, plus it locks shut. Here is an early prototype mocked up for size, etc. Now i can carry 15 extra gallons of fuel and that offers an awesome sense of security and it stores them nicely, not sliding all over the truck bed. Simply slip in a siphon hose and the transfer is quick and easy-- and no need to dismount the gas cans.

 

 

 

I also recently added a high-lift jack mount to the rear of the trire gate..

 

 

 

mb in reno

[cbfount]

My low fuel light comes on right about the time I finish coasting off to the shoulder after running out of fuel!

 

 

Yes, this tank is ridicuously small. Any good experience with Transfer Flow's replacement tank?

[whitesnake01]

I've got the 34 gal tank with my long bed dmax. The computer numbers are not very reliable (always overly optimitic). Here is what I've observed on my particular truck. Tank empty light comes on at 28.5 gal regardless of what the computer says, which means I have about 5 1/2 gals left. The computer can tell me its used anywhere from 23 to 29, moreoften towards 23.

 

I've determined that the quarter markers are crossed at 3, 10, 16, 22 and 28.5 respectively. I am referring to actual numbers as opposed to happy dic numbers.

 

My yellow fuel low light appears to be pretty reliable. Once I figured out the correlation between the yellow light and actual gallons I have been able to safely drive to a pump station even though it feels risky.