I have an occasional popping noise under the hood after I start her up. It only does it now and then but when it does it gets your attention. It kink of sounds like belt slap but they seem tight. What do you all think?

Thanks! Usta

 

air conditioner compressor clutch? that system also cycles when in defrost mode [and you can't control that]

 

It does not sound like the typical clacking noise that the compressor would make but it could be. It sounds more like driveing over a rock on the drive way type pop.

Thanks! Usta

 

Yeah, I think it's the A/C compressor. I'm having mine looked at next week; sounds like it's going to tear off when it engages!

 

The reason I don't take it in is because it only does it once in a while. I thought for a while it was my rear end because it did it once after I put it in gear and rolled backwards. Like I said it sounds like the pop when you run over a rock on a hard surface.

Confused! Usta

 

He is right, air conditioning compressor. Mine has done that for years. Turn the air off and it will not do it. Turn it on going down the road and you don't hear it because of the road noise. The first time it turns on it makes a bang and if that is after starting and as soon as the ASD relay turns on the system, you hear the bang.

 

Yeah, well... that's why mine's going in. You can hear it even at 80 MPH! And feel the drag on the engine.

 

Glow Plug relay. Makes a nice popping sound..

 

 

It is after I start the truck not while waiting for the glow plug to go out but nice try. It must be the compressor but it does not do it all the time is the strange thing.

Thanks! Usta

 

****, that's what is wrong with my truck. It is missing not only the Glow Plug but the Glow Plug Relay also!!

 

New guy here. What transmission do you have? Ive noticed the noise comming from my G56 when I take it out of reverse. My truck also makes that Pop sometimes when I start it. I had a friend stand outside my truck and listen and he said it sounds like it is comming from the bell housing. Drove another 2005 3500 with the G56 off the lot and is seemed to do the same thing. It almost sounds as if the transmission is loose and moving.

Don't know if this is the same sound you are hearing

 

I second the heater grid relay. And it will continue to cycle a little while when cold and below 18 MPH

 

I just had it happen on the way home doing around 34 miles an hour. I thought I hit something in the road but I saw nothing in the rear view mirror.

Usta