How far after fuel light comes on?

21 gallon tank, mine takes about 18 gallons when the light comes on.
I usually never go below a quarter of a tank before I refill. My oldest brother likes to run on fumes and has replaced more fuel pumps than anyone I know.

 

I hit the trip, assume 2 gallons are left and stay under 40 miles. (but typically find a station sooner)

 

Just keep going, it’s a challenge
That warning light is for chickens, keep going

 

The “Dude” would do it. That dash light was put there by “The Man “, dude

 

you just randomly decided to ask for clarification on a question asked 10 years ago?

 

11. This is 2024.

 

I've never seen the low fuel light. If I ever do that means I have 2-3 gallons in the tank. It isn't a good idea to try to drive with it that low except in an extreme emergency. I'd stop at the 1st fuel stop. The truck may keep running on level ground, but with that little fuel it will all shift to either the front, or rear of the tank if you have to drive up, or down, an incline and the fuel pump may not be able to pick up fuel.

I don't wait until I'm much below 1/4 tank and often fill up closer to 1/2 tank. I buy fuel when it is the most convenient for me and where I get good prices instead of buying it when I have to have it.

 

Gas Buddy is a good app to have to check fuel prices around you. Being crowd sourced data it's not perfect, but I find it correct more often than not.

 

Pro tip: When traveling in the desert southwest (or anywhere with few gas stations), never let your gas fall below 1/3 tank. I was driving a 4Runner in west Texas and wasn’t paying attention to the fuel gauge, and the light came on. I turned off the A/C and slowed down to 40 mph or so, trying to conserve gas. The engine died as I rolled into the next gas station. While I was refueling, another guy walked inside, came out with a portable fuel can, and used the pump next to me.

 

Overland tip: carry a full jerry can

Common sense if you're gonna try to stretch your needle too

 

https://www.youtube.com/watch?v=TuEdU_lrtZk

 

why keep the tank half full at all times minimum so you are ready for anything that comes your way

when you can run it empty stranded on the side of the road and burn out an expensive and hard to access fuel pump

when I shared my dads car to get to school as a kid, it was not explicitly stated
“If you are lazy run it to E and make me late to work in the morning having to get gas I will slap the shit out of you”
If it was stated, it would be understandable

 

“….when I came to, the car was in a ditch and the tank was full!”

 

Can confirm about 4 gallons left when light comes on. I've filled up just after the light lit, usually about 17gal.

One time on a long trip, I made a string of dumb decisions (i.e. not carrying a jerrycan, passing up gas stations before driving through BFE with a heavy trailer, etc).
Ended up with a low fuel light shortly before the fuel stop I **planned** on stopping at was closed down.
My butthole puckered harder with every mile ticked off, grannying this 5500lb trailer along, praying to see some lights on the horizon.
Finally rolled into another rest stop 40ish miles up the interstate

....and pumped 20.5 gallons into the tank. Never again

 

It’s definitely not good for the pump to go that low. I used to make fuel pump control modules and the pump is definitely cooled by the fuel it sits in. You’ll shorten fuel pump life regularly driving around with the light on. I tend to stay above 1/4 tank.

Over voltage testing was interesting as it would make the varistor red hot but don’t worry, there’s not enough O2 for an explosion.