Hey guys need some opinions on what might be causing this. Went on trip for Thanksgiving with the truck. Just got it a couple weeks ago 1997 F250 7.3L 4x2 crew cab, short bed. I was on the interstate running at 75 mph and the truck made this weird feeling I thought I had a tire going flat cuz the whole truck was shaking. Just for giggles I hit the tank switch and chaged from the Rear to the Front tank because the truck was slowing down. After about a mile of my butt sucking up the seat ... lol ... it picked right back up and ran fine. So got to Georgia and filled the rear tank up and it only took 12.37 gallons the guy I bought it from told me they were both 19 gal tanks F & R. On the way back was running on the rear tank again and it did it again .. showing 1/4 tank but it ran out of fuel. From the receipts the guy gave me he had a lift pump put in it last year due to a fuel leak but it didn't say which tank. Any ideas you can give me as where to start?? I took the spare down last night and beat on the tank and it still has fuel in it by the sound.

Thanks,
Brian

Oh BTW ... got 19.79 MPG on the trip doing 75mph not bad!!

 

maybe its sucking up some trash or algae on the pickup tube when it gets that low. most poeples truck are just the oppposite of yours we all have about 2-4 gallons left once it shows empty.
tank sizes 1
fuel tank sizes 2
you may need to drop the tank soon.

 

Is there an electric pump in these tanks or just a sender and sock?

 

no the fuel pump is mechanical. its under the turbo pedistal.

 

oh .. ok ...

well you may be right then about having to pull it down soon.

 

talked to my buddies at the local Lincoln dealer. He had a sender there to look at. He said that they bottom sock might have broken off and that wouldn't let me get to the last 3-4 inches of fuel. Anyway ... the tank's got to come off either way. Tanks are a pain.