I have an '01 2500 4x4 with auto tranny and get 12-13 on the highway and under 10 around town. I put a raptor 100 fuel pump on (fuel pressure is 19/20 at idle, 12 at wot), adjusted the valve lash, cleaned the air filter, changed the fuel filter, it has an intake, exhaust, edge juice w/attitude. I had it on cruise at 55 on mileage setting for about 250 miles the other day and it got about 13 mpg hand calculated. Not sure what's going on but I'm pretty sure something is f-ed up. Need some other ideas as to what to look at and try and up my mileage.

 

have you changed the vp at all in the truck? Sounds like you may need a new set of injectors. I would get a set of bosh rv275's they will add mpg you want and a lil power.

 

^^^^ What he said... How many miles are on that truck? It sounds like bad injectors to me. And when you put the raptor in it was the factory pump lift pump dead?

 

Truck just turned 178k and I've had it for about 8k miles. The stock lift pump wasn't dead but it was only pushin 8-9 psi and droppin to 1-2 at wot. Where's a good place to get injectors? I'm guessin alligator? haha! I've been needin to make my way over there anyway I guess.

 

Sounds more like a weak VP44 injection pump.

 

Do you know if the vp has ever been replaced?

 

As far as I know it hasn't. The truck is set up to tow and I have a good feelin that's what it was used for before I got it. Don't really what was done to it before I got my hands on it.

 

Yeah im thinking the vp is weak, but if you are looking for more mileage as well the rv275 injectors would be a good choice as well

 

Having same problem..vp44 is 16 or 17 at idle..never changed fuel filter or air filter yet dunno wen they were changed. Can that make a difference?..truck is an auto 35s edge ez and bhaf

 

I'm right with you guys in the poor mileage club, gonna change the fuel filter tomorrow and hopefully that will help some. Getting 10 mpg around town is aggrivating.