How Empty Am I When The Low Fuel Light Comes On?

tomseeley · October 11, 2009

I just bought a 2009 Sierra 2500HD duramax extended cab long box. I love it!

It has a 34 gallon fuel tank. My old 02 2500HD dmax crew cab short box had a 26 gallon tank, that I could mostly get about 23 gallons into, and when I towed the RV, which I do a lot, I usually had to fill up about every 250 miles, esp when I was out in the boonies and diesel wasn't exactly right down the road a piece.

So I'm curious. I can't find the answer to this in the owner's manual. When the low fuel light comes on, does anyone know about how much fuel is still in the tank? I'm well aware I never want to run dry, and I certainly don't intend to cut it close if I can help it. So I'm asking...

Thx.

2000DV4.8 · October 11, 2009

It's going to vary from truck to truck, and tank to tank.

Best way, is to run it down until the light comes on, and see how much fuel it accepts.

team3-8 · October 11, 2009

I have a 26 gallon tank and when my light comes on I have around 2 gallons left. I check my range and divide by average mpg and consistently comes out real close to 2 gallons left

hockeypro1411 · October 11, 2009

I try to never let the light come on. And if it does, I had better be already pulling into the gas station. Lol

peteking · October 11, 2009

I have a 26 gallon tank and when my light comes on I have around 2 gallons left. I check my range and divide by average mpg and consistently comes out real close to 2 gallons left

I actually performed the same experiment, and came to the same conclusion: about 2-3 gallons remain when my amber bulb comes on.

pwall · October 12, 2009

If you have the DIC option, it'll let you know how much mileage you have left (approximately of course).

However, once it hits 50kms (35 miles ???) it'll stop guessing and will just tell you 'low fuel' (ie. good luck).

At least that's how it behaves in my '07.

On long trips, especially when pulling the travel trailer, I carry 2-5gallon containers of fuel, just in case.

shocktrp · October 12, 2009

When the low fuel light comes on in my 08 it usually takes 27-28 gallons to top off the 34 gallon tank. Your diesel probably also has 6-7 gallons left.

ColoradoSkiCountry · October 12, 2009

Not sure how it is with the 2500/3500's but on the 1500s the fuel pump AND filter are located in the tank itself, and require fuel to help keep it cool. Never a good idea to drive with it below 1/4 of a tank as it will cause excessive wear/overheating of the pump leading to an early failure, as many have found out the hard way.

KMGZ400 · October 12, 2009

i ran out of gas before in my suburban 5.3 i think i went about 40 miles when the light was on. yes i know im an idiot

txab · October 12, 2009

i ran out of gas before in my suburban 5.3 i think i went about 40 miles when the light was on. yes i know im an idiot

Not laughing at you 'cause you ran out of gas. Laughing at your last sentence.

You should have said you performed a "test" to find out how far you could drive on "E" We would have never known the difference.

tjg79 · October 13, 2009

I can travel about 50 miles after the low fuel light comes on in my 2001 Yukon XL. I've run of gas after about 22 miles in my 2002 Sierra. I've concluded that there is a wide margin between different vehicles once the low fuel light illuminates. There's probably a wide margin between two identically equipped trucks.

If you want to determine exactly how far you can go in your truck, carry a five gallon can of fuel and let it run dry. Of course, loads, terrain and environmental variables can combine to vary how far you can go in your own truck.

spackelman · October 24, 2009

My 2002HD, crew - 34 gal tank - when the low fuel light comes on I have 4 to 5 gallons left.

superjim · October 25, 2009

Personally, I think it is goofy to run the tank so low that the low fuel light comes on.

With the fuel pump in the tank and depending (at least partly) on fuel to help keep it cool...

Plus the chance of sucking up junk from the very bottom of the tank and clogging the fuel filter...

It just makes absolutely no sense whatever to run the tank so low on fuel.

Last time I checked there were still a lot of service stations open that had fuel.

shocktrp · November 1, 2009

Personally, I think it is goofy to run the tank so low that the low fuel light comes on.

With the fuel pump in the tank and depending (at least partly) on fuel to help keep it cool...

Plus the chance of sucking up junk from the very bottom of the tank and clogging the fuel filter...

It just makes absolutely no sense whatever to run the tank so low on fuel.

Last time I checked there were still a lot of service stations open that had fuel.

If you have been running it until the low fuel light comes on since it was new - then there isn't going to be any junk in there to get sucked into the fuel filter anyway. (Also, the fuel filter pickup is near the bottom of the tank when any crap may be hanging around.)

spackelman · November 1, 2009

Personally, I think it is goofy to run the tank so low that the low fuel light comes on.

With the fuel pump in the tank and depending (at least partly) on fuel to help keep it cool...

Plus the chance of sucking up junk from the very bottom of the tank and clogging the fuel filter...

It just makes absolutely no sense whatever to run the tank so low on fuel.

Last time I checked there were still a lot of service stations open that had fuel.

If you have been running it until the low fuel light comes on since it was new - then there isn't going to be any junk in there to get sucked into the fuel filter anyway. (Also, the fuel filter pickup is near the bottom of the tank when any crap may be hanging around.)

I'm bad at waiting till the last minute to fuel up. Last year I replaced my fuel pump. The bottom of my tank was spotless. Drain ALL the fuel and wiped down with a few rags - no signs of any dirt, crud, sediment. Sparkly clean. This was at about 125k miles o the truck.