Vibration from exhaust, at 1000 RPM Options

[bansell]

Dealer "re adjusted" my exhaust

This post has been edited by bansell: Feb 26 2004, 08:18 PM

[mikez]

I have a 03 GMC SIERRA ECSB Z71 5.3L and have noticed the same problem but i'm not really sure that it is a problem. I mentioned it to a technician at the dealership and he said that with the aftermarket exhaust it was probably resonance. I crawled underneath the truck one day right underneath of the muffler and that seems to be where the vibration/noise seems to be coming from. Mine only does it when it is cold. Once the truck is @operating temperature it doesn't do it anymore. However I just drove a 2004 silverado today with the stock exhaust and it is worse than mine. By the way I have the corsa split rear 4.0 tip system.

[jsmith555]

Bansell....please let us know what they say?????? Please..Please...Please

[NothinButBowTies]

I have it too, but I dont have the time to get my truck to the dealer. Since I have added the magnaflow to the truck, I am sure that they are going to tell me to take it where the sun doesnt shine.
Here is a thought, could the vibration be coming from a bad donut gasket?
Mine only does it when it is cold too, but then again, it idles around 1000 RPM when its cold too!
Another thought, If someone had a TECH II, they could set the truck at 1000 RPM idle and have someone under the truck to isolate it.

[jsmith555]

Maybe we have some bad catalytic converters?

[NothinButBowTies]

Saturday when I was changing my oil, I completely removed the flange between Y pipe and the exhaust. Bolted everything back up and made sure the flange was seated properly. The thing was sitting there ratteling at me when I went to Church Sunday morning. I think it has to have something to do with the engine cold. That is the only time I notice it.

[NothinButBowTies]

OK I am bringing this one up from the dead. I have the truck at the stealer today. The first thing the service advisor said was - you have after market exhaust. I told him that I was 100% positive it want it and he comment that there was a TSB for a "drone" at 1000 rpms. Solution? To put flexible pipe near the cats. I havent heard from him about that, all he called to say was that they were not going to recoat my front bumper.
Does any one have any more info on this?

[bansell]

I am still trying to get this fixed... The dealer is now looking for a truck with the same motor/trans combo and mine.. When they told be that I laughed and told them they had 100 trucks on the lot with the 5.3 auto 4x4...

He then corrected and said a truck with the same miles as mine.. My responce was that if it didn't do it when it was new, it should not now. I think they are trying to find another truck with the same problem to make me go away.
He will not compare with a new truck, so much for GM's warranty!

[NothinButBowTies]

UPDATE:
The heavy line department at the stealer noted that my surge tank to the cooling system was the problem
It stated on my paper work that the surge tank was inproperly installed. Corrective action was to reinstall surge tank, tourque bolts and refill coolant. If this is the problem then pigs will be flying out of my ass in the morning when I go to put in reverse.

[tdrumm]

If this really is exhaust related, flex exhaust piping sounds to me like a band aid for a bigger problem with the hanger system. If a dealer wanted to do that to my truck, I'd tell him to stick his flex up his a$$.

[NothinButBowTies]

If this really is exhaust related, flex exhaust piping sounds to me like a band aid for a bigger problem with the hanger system. If a dealer wanted to do that to my truck, I'd tell him to stick his flex up his a$$.

Well, I want to really bad, but the thing is the noise is gone. I know now that I have said this, it will be sitting there driving me nuts in the morning. I cant believe it!
When I asked him about the flex hose near the cats, he informed me that my complaint did not warrant the repair.

[jsmith555]

Hey NuthButBowTies,

Was the noise there is am after they "re-installed" the coolant surge tank?

Thanks!

[NothinButBowTies]

Hey NuthButBowTies,

Was the noise there is am after they "re-installed" the coolant surge tank?

Thanks!

No I cant believe it! That makes no sesne at all. Does anyone have explanation for this one?

[04z71burb]

I have what I think may be the same noise y'all are talking about on an 04 Z71 Suburban. It sounds like someone is banging on a cookie sheet with a hammer. Mine does it intermittantly under light acceleration. If I punch the gas down a little more, it'll go away. It's definitley some sort of resonance. This noise started happening to me at about 200 miles from new. The service guy told me that GM knows about this noise but doesn't know what to do about it.

I did find a TSB (02-06-05-005) out for the heat shield rattling against the muffler that could possibly be causing my noise. The fix for this TSB is to install straps on the front and rear of the muffler. Although, if some of you are having this trouble with aftermarket exhaust, I don't see how the heat shield is my problem.

[mmayo]

I had the dealer fix my heat shield under that tsb, some of the tac welds had broke lose, and the rattle was driving me crazy. They put that "strap" over the back of my muffler and it took care of the problem.