[03cumminsHD]

When my truck is running, I can hear a rattle coming from the dash. It last for a second or two, then quits, then comes back for same amt of time. It also does this while driving. Any ideas? This is driving me insane.

 

[03cumminsHD]

anyone????

 

[Cekkent]

Does it come and go if you switch from defrost to a not-defrost setting?

 

[SEAN06]

there is a thread in non powertrain about this,mine does it too

 

[jetfuel394]

check ur trans fill tube to see if it is rubbing on the a/c line. i found this after i chased it 4 8 mos.

 

[josh brown]

check ur trans fill tube to see if it is rubbing on the a/c line. i found this after i chased it 4 8 mos.

Same thing here.

 

[03cumminsHD]

From vent to defrost does not change a thing. Thank you for the replies.

 

[03cumminsHD]

Found the culprit, now need help figuring out what this part is. There is a black plastic piece mounted on passenger fender near firewall. It has rubber hoses that connect to it, an electrical connecter, and a cable that comes off of it and runs across top of engine under the drivers battery. Anyone know what this is???

 

[03cumminsHD]

Problem fixed. The piece that was vibrating and making the rattle was the vacuum pump for cruise. There is a small hard air line that runs from the pump over under the battery tray to the servo solenoid. It had rubbed on something and had a hole in it causing the pump to kick on and off. So some 1/4 inch fuel line and some splicing and problem fixed.