Good question. Most of the people I know who have GM trucks with the
fuel pump mounted at the tank end up with VERY loud fuel pumps once the
vehicle gets a few years on it, then eventually the pump fails.
Seems to be a very common weakness, and the replacement labor cost is
fairly high due to the need to drop the fuel tank.
The GM fuel pump is lubed and cooled by fuel in tank. Running it low a
lot will greatly shorten its life. As far as not stating it in manual,
it could hurt sales to say so and then there is the dealer revenue for
repairing it too so they are not going to tell you. I have a 89 burb
that I have had since new and still has original pump as I never run it low.
Likewise I have a '94 Silverado that I don't let get below 1/4 tank. In
fact - that's a standing principle in my household. Fill 'em up when they
hit 1/4 tank. When you live in winter climates, you quickly learn about
such things as ice in the fuel lines. All tanks have water in them as a
result of condensation and it has just been a long standing practice among
savvy people not to let the tank get below 1/4. In the summer time it can
be a simple water problem - no ice to contend with. Some water is fine for
combustion, but not the kind of water content you can be pulling up from the
bottom of the tank. Then, there's the sediment issues. All tanks have
sediment. Again - let a tank get low and you agitate the sediment much more
than if you keep it up a bit. Yes - this does apply even though the pump
feeds from the bottom.
I did replace the fuel pump in my Silverado, but only because I had to
replace the gas tank at a little over 110,000 miles. NY corrosion. Figured
as long as I had it down, I'd go all the way. My factory pump showed no
signs of weakening (they never do), and I noticed no difference in
performance with the new one, so I'm sure my factory pump was outputting
just fine. I just didn't want to have to get underneath the truck again.
Does there have to be a warning or a disclaimer for everything?
Common sense dictates keeping gas in a gas tank just like keeping oil in a
Then again there is no minimum intelligence test for car ownership hence the
use of idiot lights for every frickin fluid in a vehicle nowadays including
the gas tank and the gas cap.
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