New Lift pump (Transfer Pump) in March with less than 12,000 miles on it. My pressure is most of the time 10-12 psi but yesterday went down under 4 for a couple of hours. The rest of the day untill right before I got home it did it again. I notice no difference in performance nor was it a speed related issue. Any suggestions on what this is? I took it into Dodge, and told them they insist that until they can see it using there guage they cannot replace it under warranty. Just looking for some solid advice....I guess to me its worth changing the lift pump so I can keep the injection pump safe.

 

Dealers! Ahrg!

Did they compare your pressure reading to their gage? If it's comparable, they should believe you. If you can, take it to them when the pressure is down.

When mine was doing that, I would "punch" the pedal and it would recover. That at least kept me from driving extended periods with low pressure. I replaced it with a FASS II, and no more pressure problems.

Just wondering, how do you still have warrenty at 134k miles?

 

Just a suggestion,,, but ya might try checking all the electrical connections and buy a spare from Cummins (cheaper than DC) to keep on hand just in case. However, I have read many posts where guys have described the same symptoms (good psi,,, then bad psi,,,,, then good again) and it turned out that the LP was going bad. If cleaning the connections doesn't cure it,,,, I think I would replace it at home rather than out on the highway or go with an aftermarket cure.
Good luck and let us know what you find.

 

Sitting at the dealersip now, they have a computer here in the waiting area, nice huh, free soda. I will go out and talk with the tech on the electrical connections. Warranty is because they just replaced the lift pump this spring under the 12,000 mile deadline.

 

Well, problem resolved says the dealer. Not says me. Pump pressure still falls, but the dealer has informed me that they cannot replace my unit due to the fact that the volume not pressure is with in the spec's. Note that the pressure while it was there was fine. Guess I will go ahead and plan on budgeting one of those fass systems.