Vibration Noise on Start-up

[jarydM]

On cold start, The truck has a very noticeable metal-metal vibration sound. When I first bought the truck it came and went, and I thought there was a heat shield that had rusted and was falling against the exhaust somewhere, but was never able to locate it under the truck.

After years of having it, I have noticed that the noise is louder now, and most pronounced on the drivers side near the front. It lessens as the engine gets hot. Reading here and there, I am convinced that the noise I hear is from a broken manifold bolt.

I saw someone here recently was able to get the broken bolts out with a quick out, but from what I have gathered, that is rare. Is this a job I can reasonably tackle myself, or should I take to to an exhaust shop?

and secondly, if I do that, should I just get headers for it as well?

 

[cmc76]

you should always get headers.
sadly, ive yet to have an excuse to do so.

 

[PG01]

Im guessing it depends on your mechanical ability, how many are busted, if you want to scrape up your knuckles and want to do it for the satisfaction of doing it. If you really want headers, yank the manifolds pull the bolts and there ya go.
Forgot this.....
And this .....
And this......

 

[jarydM]

Im guessing it depends on your mechanical ability, how many are busted, if you want to scrape up your knuckles and want to do it for the satisfaction of doing it. If you really want headers, yank the manifolds pull the bolts and there ya go.
Forgot this.....
And this .....
And this......

I'm pretty handy with a wrench, one of the draws of this model of the Tahoe is the ability to (still) be able to do most of the work on it in the garage. I guess my question should be framed more, if I go to the effort of pulling off the headers, should I just replace them?

I think the Driver's side Cat it broken up after a failed O2 sensor problem (can hear pieces rattling around), and i think the headers have more bolts broken than before. Is it more worth it for me to have a shop do headers and cats, or try to do it myself? End goal would be long tubes, and Corsa, but I'm not ready to throw down that amount of cash if I can avoid it.

 

[rockola1971]

From what I am reading you dont know for sure that you have a broken manifold bolt. Is that correct? You are putting the cart before the horse. A broken manifold bolt does NOT make any noise. The manifolds dont move around and rub on the manifold bolts.

 

[jarydM]

From what I am reading you dont know for sure that you have a broken manifold bolt. Is that correct? You are putting the cart before the horse. A broken manifold bolt does NOT make any noise. The manifolds dont move around and rub on the manifold bolts.

you're right, I'm not SURE that its the culprit, but I've been up and down the exhaust under the car, and can't find anything else. I don't think its rubbing on the bolt, I think one on an end has broken, which is causing the whole maifold to vibrate against the engine, and the sound goes away (mostly) once the vehicle is warm, and the metal has expanded a bit.

this is mostly all conjecture, and educated guess I've made from other people having the same complaint on similar vehicles (silverados, yukons, etc)

 

[rockola1971]

you're right, I'm not SURE that its the culprit, but I've been up and down the exhaust under the car, and can't find anything else. I don't think its rubbing on the bolt, I think one on an end has broken, which is causing the whole maifold to vibrate against the engine, and the sound goes away (mostly) once the vehicle is warm, and the metal has expanded a bit.

this is mostly all conjecture, and educated guess I've made from other people having the same complaint on similar vehicles (silverados, yukons, etc)

The rest of the bolts hold the exhaust manifold onto the head. If one were broken i guarantee you the rest of them arent going to allow manifold "to vibrate against the engine".
Common problems on these chassis is the cats making noise from their cores rattling, exhaust hanger on the rear missing, broken, rubber buffer missing, damaged exhaust bent toward floorboard, exhaust manifold bolts broken at extention connection where the donut sits if equipped.

 

[traveus]

My 07 suburban does this. Always when I'm barely touching the gas. It's so annoying, I can't figure out where it's coming from.


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[Fleetgeo]

I have the same thing also on my 01 GMC Yukon Denali 6.0 when I turn it on in the morning and take off with it In drive as I slowly tap the gas you hear a vibration noise sounds like it's coming from exhaust idk but it's annoying

 

[about20ninj45]

Mine did that, it was a busted cat. I just drove it like that and then it shot itself out one day. Didnt bother to replace it, because my state doesnt have emissions testing