That normally isn't a problem on fuel injected motors...the electric pump and return line all but prevents this.
However, hot conditions and a weak pump can do it. Check your fuel pressure. You should have a valve like a tire valve. You can go to the dreaded Auto Zone and rent a guage. Check with a service manual and see what it should be...bout 35 if I remember correctly. If it is low, even just a little, replace it.
Also, it may be easier to remofe the bed, rather than drop the tank. Look into it. I know this to be true on a smaller @ss-10 truck.
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The hot rod; a'69 G.M.C. Short/Fleet. 350 W/a heluva cam and nice stance. Still a beater though. Trying to clean up the left over damage from the Dope-Smokin-Old-Man...a real bummer. See it at
http://geocities.com/andys_69_gmc/
The not rod; old beat up Mighty Morphin Power Ranger. (that's the ONLY cool way to say pos Ford Ranger)only purchased it for the gas mileage. (at least it's a V-6) And now it's for sale...2500 bucks or trade for inline '67 - '72.
I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. Check out my Longhorn site at <A HREF="http://geocities.com/MotorCity/Flats/8752/
" TARGET=_blank>http://geocities.com/MotorCity/Flats/8752/
</A>