Last time I drove the truck it was fine, sat for a couple of weeks and no start.... After turning it over forever it started a couple of times but only ran for a few seconds. Can hear either fuel pump run when ignition is turned on. So far I have replaced the fuel tank selector switch ( it had gone bad before), also tested for fuel pressure and the gauge showed 0 lbs for both tanks. I am reasonably sure that one pump has been bad for a couple of years anyway as the truck would barely run on it. Before I go and spend $$ on a pump is there any thing I should try first?

 

If you tested the fuel PSI before th4 filter and pressure regulator and got 0 psi, the pump is probably bad. If you tested the fuel line after the filter or fuel filter, replace those and try again.