Strange Problem

Two possibilities... your tank's vents could be blocked, causing a vacuum in the tank, which will eventually prevent the pump from drawing fuel. When it happens, remove your gas cap, and listen for air rushing in.

Or, there's a hose between the fuel pickup and the pump. If this hose develops a crack, when the fuel level drops below the crack in the line, the fuel pump will start sucking air instead of fuel.

It's possible, but you don't want to destroy your bed like that. Dropping the tank isn't really that hard, if it's relatively empty. A floor jack and a piece of plywood will support the tank, and two bolts hold the straps on.

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Does your name stand for Dimethyl Sulfoxide ?

You can ask your question about your son's truck even if it is a ford. Most here don't care and if they have the answer, will share it with you. This group is unique in that manner.

Roy

If you're going to cut the hole in the bed with a torch please have a video camera running. It might make for some great TV.

beekeep

David,

In case you get into the situation where you are about to drop the gas tank to access the fuel pump:

I did this about 6 or 7 years ago on a friend's '96 1500 SB, and there is an easier way. On this model, the fuel pump cartridge was mounted very much forward in the tank. I found that all I had to do was disconnect the fuel filler hose, unbolt the rear bumper, take the four (I think) bolts out that hold the bed to the frame, and maybe disconnect/unclip a few wires and tubes.

Then I just slid the bed back about a foot on the frame, and the fuel pump could be reached from above, right behind the cab. Don't remember for sure, but I believe it wasn't even necessary to completely remove the bumper, just rotate it down enough to let the bed slide back.

Martin

Another advantage of this technique is that you don't have to empty the gas tank.

Martin

Oops - got dyslexic - no need to unhook the fuel filler tube - tank stays put. I've done it both ways, sliding the bed on a pickup and dropping the tank on a van.

Martin

If you don't unhook the fuel filler tube, how exactly do you intend to slide the bed back?

You're right, I was trying to type while actually getting something done here at work, and messed up. Call it mental dyslexia. Plus, it's been seven years since I did that job, and I only did it once (not my real line of work). But believe me, it was much easier sliding the bed back on that pickup than dropping the tank on the van.

Martin

I bet that it was and sliding the bed back is a great idea. I'll have to look into doing it that way myself.

Try it both ways before you judge. Sliding the bed was a one-man job on the pickup, while dropping/replacing the tank on the van required a helper to hold, support, and position.

Martin