title says it all. i can pinch off the return line and it shoots up from 40 to 60 at idle with the pulses of the lift pump. i changed the fuel filer, the screen on the heater. and i shimmed up a over flow valve so that i have 28 or so at idle. am i just at the limit of the stock fuel system? do i need to ad a aux. system? i have a dyno day saturday i was wanting to hit but the truck just doesn't run as hard as it did and it is really starting to bug me. anyone have any ideas. it has a set of dynomite diese stage 4s, lots of rack travel, 181 delivery valves, a hx40/16 on top and a bht3e on bottom with a 26cn housing on it and a 2.9 inducer on the cold side.
the truck was all but insane to drive 3 weeks ago. i would roll into it at 60 in 3rd locked up and start spining tires. all i have left to do is drop the tank and take a look at what is going on. it was running well and now it is just weak and it is driving me crazy.

 

??????????

 

Sounds like your pump might be going out. I dunno much about the 12v's. I'm fortunate enough to have a 24v that tells me when my lift pump goes out because it takes the injection pump with it. Adding an auxillary system can't hurt anything.

 

Try Haisley's aux system.

Jim Fulmer's had a lot of success with it. It's simple and works.

 

Well... I pick up my 4090046 transfer pump replacement kit. $70 including Uncle Sam's tip... No questions asked.

I will be testing my original again when I do the oil change. This looks like a fun job, has anyone replaced the lift pump on the 01 here?

I'll do a search anyway... At first glance it looks like a knuckle buster for sure.

 

i hear that! i just went through another vp44 yesterday