2007 Tahoe 5.3L
How long are any of you getting on your fuel pumps? Sixteen years old and 253,000 miles and planning a 1300 mile cross country. I will probably change it for my peace of mind but I'm curious on their longevity. Thanks.

 

never needed to change a pump in my life. Current one is 11.

 

I've read that the best way to extend the life of an electric fuel pump in the tank is to never let the tank get below a quarter full, especially in the summer, because the fuel keeps the pump cool. I don't know if that's true but it does make sense.

 

If it ain't broke,don't change your old friend - just getting broken in!!

 

I looked into it once, and it's not exactly true ....


Fuel does keep the pump cool, but it has nothing to do with the level in the tank.
The pump is cooled by fuel flowing THROUGH it. Not the fuel sitting around it. The coolant in your engine has to flow to do its job too.

When you tear a fuel pump apart, you can see it's designed that way:
The pump is small -- about the size of a salt shaker -- and the parts are made of metals with good heat conductivity . That makes it easy to cool .
The fuel flows through the inside of the metal pump body, and surrounding the armature. That means that the motor windings and laminations (the part that actually generates the heat) are always in DIRECT contact with the fuel. The few joules of heat generated there are quickly carried away by the fuel to your engine.
The pump is always sitting in its own bath of fuel, which has a check-valve. It has to, or else your car would stall during cornering! It doesn't need the thermal mass of the entire tank.


The reason they used to tell you not to let your tank get too low, is because fuel tanks were all made of steel back then, and the rust and junk would collect at the bottom. You didn't want to swirl it up and get it sucked into the pump.
Most tanks are plastic now so they don't have that problem.
The other obvious reason is you don't want it to get so low that the pump sucks air or you stall!

But I personally think there's nothing wrong with filling up when the gauge gets to 'E' , just like the owners manual says. That's what I've always done (and probably pushed it on more than one occasion), and like I've said I've never had to replace a pump.

 

We've had 1988 Suburban, 1994 Sub, 2005 Yukon, now have 2014 Yukon, all purchased used with 85-100K miles on them at that time. We've not had a fuel pump issue, and with the reported issues/cost savings programs with parts the last few years, I'd be skeptical of throwing money into lower-quality replacement.

 

Thanks everybody. I will stay with the original pump.

 

"Never trouble trouble until trouble troubles you !!!" - Yogi Berra, or someone else