I would stand alone the pump before I changed it just to be safe. Vp pumps got a bad wrap but their really not that bad. In the lifetime of most trucks in these parts we only see 1 pump replacement. With a FASS or quality fuel system failure is actually pretty rare. It does sound like a pump though, it might be worth mentioning that the main reason for aftermarket lift pump systems favor 15psi or higher is to improve injection pump cooling. I've found that at less than 12-13psi there's significantly less fuel moving through the pump above idle. P-pump swaps (imo) are not worth the cash it takes and the truck looses some aspects of its driveability. But if you order a kit I'd look at pure diesel power!
