I would have to say the lift pump is the weak link on the fuel system. My conflict is, unless they have changed the in tank pump, I don't like the pressure it puts out. The pump on the side of the engine runs 10-15 psi, and the in tank runs 0-5 psi. I've heard the VP44 likes 10-15psi. I've kept the pump on the side of the engine on my 99. I've only had 1 start acting up and had to be replaced in 225000 miles ( I know that may vary). The other reason i've kept w/the original pump is you are limited where you get the in tank if it goes out. You can get the original from Cummins, autozone, advanced, etc. and is usually cheaper. If I were still under warranty and didn't have anything really wrong, I would try to find a way to have them adjust the valves under for free. I've had mine done between 150-175000, but ,i've seen some that tow more than me need theirs done around 100k.