Low Fuel Warning

[834k3r]

First off, I apologize for any duplication of thread material here; I searched and saw no pertinent threads, but I don't want to be "that guy."

So, we're all familiar with the low fuel light that dings at around 50 miles remaining on the tank. Last night I was towing our camper trailer back from a baseball tournament and I got no warning light (as in it did not ding or light up to warn of low fuel)--even getting to an estimated range of 35 miles on the tank. Got me thinking about two things:

1. Has anyone figured out or found the fuel level at which the fuel tank will announce low fuel? Knowing that would be helpful for travel planning.
2. Why didn't my low fuel light activate last night? Theoretically, with a lower fuel economy towing the trailer the fuel warning should have kicked off above 50 miles remaining if it's driven by fuel in the tank and current MPG. Seems silly if they warning doesn't activate when towing (trailer connected, in tow/haul mode).

Thanks in advance for your thoughts.

 

[Sascwatch]

Mine comes on around 80km or 50 miles no matter the situation. Towing or empty it’s always been the same.

 

[CrazyWorld]

Mine does as well.......but.....I rarely let it ever get even close to that low.

 

[User_3336]

Never let your truck's fuel level get to the point where you're guessing.........Query solved.

 

[Nsleone]

First off, I apologize for any duplication of thread material here; I searched and saw no pertinent threads, but I don't want to be "that guy."

So, we're all familiar with the low fuel light that dings at around 50 miles remaining on the tank. Last night I was towing our camper trailer back from a baseball tournament and I got no warning light (as in it did not ding or light up to warn of low fuel)--even getting to an estimated range of 35 miles on the tank. Got me thinking about two things:

1. Has anyone figured out or found the fuel level at which the fuel tank will announce low fuel? Knowing that would be helpful for travel planning.
2. Why didn't my low fuel light activate last night? Theoretically, with a lower fuel economy towing the trailer the fuel warning should have kicked off above 50 miles remaining if it's driven by fuel in the tank and current MPG. Seems silly if they warning doesn't activate when towing (trailer connected, in tow/haul mode).

Thanks in advance for your thoughts.

Should be coming on with approximately 3-4 gallons left in the tank if my math and logic is correct. There might be an exact number in the owners manual. I see what you’re getting at for towing but I don’t know if the range estimate and the fuel level talk to each other. In other words, I don’t think the fuel level sensor knows what kind of mileage you’re getting. So if you’re MPG is 10 for example, a 3 gallon warning light won’t come on until you’re at 30 miles of range. I could be completely wrong but this is my hypothesis to your scenario, some digging in the owners manual might find the answer!


I run my truck down the the fuel light often since I have the transfer tank in the bed, no panic feeling for a gas station. My light usually comes around around 60-70 miles range and I average 17.5 mpg empty.

 

[OldMarine]

my low-fuel light is always on after my wife has borrowed the truck ....

 

[devildodge]

Keep in mind while towing. The fuel in your tank also cools the fuel pump. You want to get fuel sooner than later.

 

[834k3r]

Keep in mind while towing. The fuel in your tank also cools the fuel pump. You want to get fuel sooner than later.

That is not only something I didn't know, but very good to know.

Should be coming on with approximately 3-4 gallons left in the tank if my math and logic is correct. There might be an exact number in the owners manual. I see what you’re getting at for towing but I don’t know if the range estimate and the fuel level talk to each other. In other words, I don’t think the fuel level sensor knows what kind of mileage you’re getting. So if you’re MPG is 10 for example, a 3 gallon warning light won’t come on until you’re at 30 miles of range. I could be completely wrong but this is my hypothesis to your scenario, some digging in the owners manual might find the answer!

My sense is 3 gallons is probably close. Also, your math checks out; mine doesn't (there's a reason my undergrad degree is in political science instead of engineering). Lower MPG would equal a lower number of miles displayed when the warning activates.

All: I don't intentionally run my gas tank to vapors. In fact, it stresses me out to do so. But there are times when it's helpful to know what the truck's got--especially out here in the West where gas stations aren't as close as they are further east.

 

[devildodge]

That is not only something I didn't know, but very good to know.

Also. When going up a hill...the fuel pump is at the front of the tank. So also, you can run the fuel away from the pump at the time it needs it most.

Best bet to be finding a gas station when you hit 1/4 tank. Especially since towing in weather can drastically change fuel mileage in a way the computer can not keep up with.

After 200 miles I am looking for a reason to stop anyways.

Just some thoughts.

 

[HSKR R/T]

Keep in mind while towing. The fuel in your tank also cools the fuel pump. You want to get fuel sooner than later.

Why would it matter if he was towing or not? Also, the fuel pump sits inside a "basket" that is full of fuel. And as long as there is fuel flow through the pump, it is being cooled, and lubricated since the fuel also provides lubrication for the pump. Fuel level in the tank has little effect, unless you actually run it completely empty.

 

[HSKR R/T]

I usually just watch the range display, and don't worry about low fuel light. I almost always run mine down to around 30 miles left in range before filling up. Have even ran it past 0 a few times just to see how far I can go after hitting zero. With a 26 gallon tank, I have never put more than 24 gallons in it

 

[devildodge]

Why would it matter if he was towing or not? Also, the fuel pump sits inside a "basket" that is full of fuel. And as long as there is fuel flow through the pump, it is being cooled, and lubricated since the fuel also provides lubrication for the pump. Fuel level in the tank has little effect, unless you actually run it completely empty.

Guess i am wrong. Learn something new everyday. Ignore my comment. I am unaware.

 

[HSKR R/T]

Guess i am wrong. Learn something new everyday. Ignore my comment. I am unaware.

It's something many people think, and spread to try and "warn" others. Usually stems from them having a fuel pump fail shortly after running the tank low. High HP race cars usually run external fuel pumps. So if it was true the pumps need submerged for cooling, those pumps wouldnt last one drive.

 

[devildodge]

Your right.
I learned to keep the fuel level above 3/8 on my 99 while the fuel pump was failing. And on the camping trip that I found out it was the fuel pump that was failing. Pouring a fresh 5 gallon on the fuel pump got me home.

Again. Ignore my comment. Guess my comment about the fuel flowing to the back of the tank and starving the pump is wrong too.

Sorry for giving this man wrong information.

I guess it is just an urban legend