Name that noise...

[95obschevy]

Alright so this noise has been buggin the hell out of me so hope you guys can help. Every day om driving my 95 and I begin to come to a stop I begin to hear a rattling noise coming from under the truck which gets louder the closer i come to a stop. This noise is immediatly followed by a clunk noise then the engine surges. As soon as i start to let off the brake the rattling starts for a brief second or two and goes dead quiet as I accelerate. It only does this when the engine is up to temp. what is it??? heat shield? u joint? idk please help.

 

[sewlow]

Does your truck have a factory 'Gov-loc' posi unit? They tend to make loud ratcheting noises like that.

 

[95obschevy]

Does your truck have a factory 'Gov-loc' posi unit? They tend to make loud ratcheting noises like that.

Yeah it has the G80 if thats what your talking about

 

[sewlow]

Yup. G80's & G60's all make that ratcheting sound. It's normal. They have a tendancy to lock when you don't want 'em to, & not lock when you do. They also like to go boom, (as in fail) with moderate to heavy abuse.

 

[95obschevy]

Hmm so that probably explains the clunk. Is there anything you can do to those to stop the noise or is it pretty much live with it or replace it kinda deal. Im pretty sure the rattle is coming from underneath the passenger seat so im guessing thats the heatshield or the cat? And then I figured out the surging in rpms was due to a vaccum leak from my cold air intake.

 

[sewlow]

Yea, pretty much gotta live with it, or replace it.
Still have the stock muffler? They rattle when they're on the way out. Give a couple of good taps with something, & see if it makes the sound. Heat shields will rattle too.