Patman

Are you saying that people that fill up at 1/4 tank are going to have a fuel pump failure? At that point you're still ok, it's the people that constantly run it right down to 1 gallon or less that will have issues. But filling up at the 1/4 mark or higher is not going to be a problem. I have generally done that with every car I've owned and have never had a fuel pump failure in 33 years of driving.

Gearhead Jim

A pump engineer told me that electric fuel pumps are cooled by fuel flowing through the pump, not by the puddle of fuel around the pump.
He said the overheating problem comes when you run completely out of fuel, then the pump continues to run with no cooling fuel going through it and burns up very quickly.

Lots of people routinely run their fuel down until a warning light comes on, but they don't seem to suffer any more failures than the rest of us.
Heck, for many years my wife didn't even know where the gas gauge on her car was located, she'd just drive until the warning light came on and then gas up when convenient. It took me a couple of decades to convince her that if she actually ran out of gas it would cause big problems, but we never replaced any pumps.

JMII

I've done this for the last 16 years on my Dodge Dakota 4.7l V8 - no problems at all. My take is if there was a real possibility of serious damage to the pump the OEM would make the low fuel light come on earlier.

eseibel67

You guys make some good points. I also run the tank low even though I was taught that the pump will last longer if its submerged. Now when I run it low Ill feel ok about it.

Gearhead Jim

Having said my piece about low fuel not hurting the pump, I'll also repeat an old aviation saying:
"The only time I have too much fuel is if I'm on fire."

I routinely fill up just below 1/2 tank because I've had sudden events where I had to go some distance without time to gas up, or the gauge just could be inaccurate, or the electricity goes out and none of the local stations can pump gas. Etc.

Kevin A Jones

There are literally hundreds of different "in-tank" fuel pump designs in today's cars and trucks and some are more at risk for low fuel failure than others. However, the majority will benefit both internally and externally from
improved cooling as a result of consistent higher fuel tank levels.

devnull

C'MON THELMA!

robert miller

devnull

Coming from that ZLE (I averaged 10.7mpg for my tenure there), this sucker is freaking efficient, and I forgot what that was like Robert! HAHA.

7thgeneration

Running the pump too low on fuel will eventually cause a failure. Don't ask me how I know. And no it was not with a Vette.

CP

With all this computerization in this car, why, oh why, do we not know how much gasoline is in the tank EXACTLY, and the point at which the intake will "suck air"?

Patman

That's what I've been wondering, it seems it would be so simple to have a separate reading in the DIC that says exactly how many gallons are left, right to the tenth of a gallon.

Gearhead Jim

Modern airliners have capacitance fuel gauges that are extremely accurate over a wide range of conditions.
Maybe too expensive, or maybe "we've never done it that way."

Kevin A Jones

All vehicles have had fuel gauges since the beginning of automotive history and most modern vehicles also have a low fuel warning indicator and this has always been good enough. I don't understand why anything else is needed?
Gees, just watch your fuel gauge and/or low fuel indicator and refill at whatever point you feel comfortable doing so.

Patman

I think it's because with a lot of cars, once the gauge hits empty and the light comes on, there are often still as much as 2 gallons of fuel left so it's human nature for some of us to want to know EXACTLY what's left in there, especially if you're in the middle of nowhere and want to know if you can at least be a little bit more picky about the station (looking for a Top Tier one perhaps) or if you need to fill up NOW. Plus I always feel when it comes to cars, the more information you can get the better. That's what's nice about the C7, it does give a bit more info than most cars do (such as tire temps, transmission temp, total engine hours, 0-60 times, G meter, and so on) but even more would still be cool to have.

grinder11

I've read on the forum that if you routinely run the C5 below 3/8-1/2 full, it can mess with the sending unit when left for long periods of time without refilling. I don't know. Mine is now 20 years old, and is starting to act up. Not much warning when down to the last 2 or 3 gallons when the gauge shows half full, then nosedives to "E"!! But I cut my teeth on motorcycles that had no gauge. I just reset the trip meter, know my mpg, and drive accordingly