Ok, this has been going on for awhile now. I leveled the truck about a yr ago. thought maybe its something to do with the fuel pick-up in the tank... Around 1/4 tank mark, the truck seems to lull like its not getting gas every time I start from a stop... and again when it wants to shift gears. (nose dive and lose of power) = really annoying! filling the tank solves the problem. So another theory was that the gauge was off somehow. (dismissed that theory due to gas milage and quantity of fuel that fits in the tank.) but still thought i should mention it. Is there a way to reset the gauge? (tried disconnecting battery...nothing) I guess i'm just wondering if anyone has come across these simptoms before and what did you do to correct it>? thanks in advance. Mark

 

when is the last time you changed your fuel filter?

 

What's a lull?

 

Hmmm, not sure, haha, just always used that term to describe what it is doing...

Lull\, v. i. To become gradually calm; to subside; to cease or abate for a time; as, the storm lulls. (from dictionary.com )

I guess it still makes sense. But ya, come to think of it... I'll try the fuel filter thing. been almost since I changed it last summer (20,000K ago)
Talked to another mechanic about it, another theory is that the fuel pump itself has come loose in the tank and is kinda floating around in there, not sure how these pumps are set up, but he's a mechanic at a ford dealer and has said this has come up a few times through the shop. might be a production thing. anyone heard of this? thanks, Mark

 

I would try fuel filter before fuel pump floating around in the tank theory. I have not personally heard of it.