I have a 04 CTD 48RE and when I let off the throttle{speed does not seem to matter} I get a thump noise,feels like it is under the hood or in the front of the trans area. The truck does need to be pulling to make the noise and it is not much of a noise at that, the radio needs to be off to hear it and the windows up. Shifts great and no other problems, been watching this site and seems like a great one, so what do you all think? heard of this before or is this a new one? Thanks for the help.

Scott

 

Could be turbo bark. If your going from high boost to no boost that will happen. Bad on the turbo. Just let off the throttle easy and it shouldn't happen if thats what it is.

 

I got that exact noise! I thought it was the u's. But it was'nt. Happens with VERY little boost too-any gear. It sounds like when the u's went out in the 99'

 

It drives me crazy, the wife can not hear it and says I should just turn the radio up and I know if I take it to the dealer they will not hear it or just tell me it is "normal" when they probabily will have no idea what it is. I sometime worry about the small stuff.............

 

Tell me about this turbo "bark" or "chuff"? I am told this is common in turbo gas stuff, The boost hits the throttle plates and slows the turbo but had not heard of it on diesel.

 

Sounds like it may also be a motor or trans mount.......

 

drivetrain slack/backlash???

 

Check your motor mounts...a friend of mine just found a loose one on his new 04.5

 

Yup, that would be "ME"