Just like the title says, I was sitting at a stop light today when my engine just died, like i ran out of gas. I switched to the rear tank, and all was well. I drove to the nearest gas station (I didn't think i was out of gas, but i have a new gauge cluster, and it was a little low) and put in 3/4 of a tank. It ran fine on the front tank. Got on the freeway and once i got up to speed, it sputtered and died. I switched to the rear tank, and she lives again, right away I switch back to front and it's fine for a few min, then it does it again. Truck is an 1989 f150 5.0, with an AOD, 2x4, 67,000 miles.
I'm thinking it's:

A connection problem, I recently put new sending units in, and a new gauge cluster. When I did this, I cleaned all connections very well.

The fuel selector valve, I have had problems with this, the rear tank fills the front tank on the return, but it will switch from front to rear without problem. Could it be that the valves are getting stuck partially open or something?

The front fuel pump, it is a junkyard special, and it does hum sometimes. I bought it with the sending unit, thats why I didn't buy a new one.

 

Well, I replaced o-rings in the selector valve and it seems that all is well. I'll let anyone know if i have any other problems