Truck wont strat on less then 1/4 tank of fuel

[usmcgriff]

I have an 03 6.0 and when it get below a 1/4 tank it getts really hard to start. yesterday i had about an 1/8 tank and about 40 miles left on the computer. and the truck almost would not start then it was missing and was shacking like crazy. then i water in the fuel light came on. I have filled it back up and it is starting fine now but the water in the fuel light is still on. any ideas

thanks

[bigcountrysg]

I bet your fuel gauge is off. Mine is and I only get about a mile or two once that low fuel light comes on.

Drain the fuel water seperator on the engine. Then add some fuel additive into the fuel tank. I like seafoam for water in the fuel problems.

[kurp22]

your suction line could have a pinhole in it, once the fuel level gets below ythat mark your sucking air. kinda explains the missing and shaking. you will probbly have to replace the sending unit in the tank