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Unusual exhaust noise

XTOAK

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XTOAK Enthusiast

XTOAK

Posted
Posted

I took my truck in to the dealer and they said they couldn't find where the noise was coming from, and that they had checked the diff fluid level and everything looked fine. Told me to take it home and "we'll see if anything develops".

 

So, maybe someone here can help.

 

The sound is like that when you blow across the top of a beer or coca cola bottle...it is only under acceleration and occurs no matter what gear you have it in including park. I can be going down the road, shift it into neutral and give it some gas and still get the "foghorn" sound as my son calls it. It is only when I'm under 35 mph. It is only for the first five minutes when driving and then goes away. Has anyone else experienced this?

Shaners Senior Enthusiast

Shaners

Posted
Posted

Sounds like a heat shield. Once everything warms up and expands it must be going away....

 

Some people have put some fire-proof insulation in between their shields and the exhaust to keep them from rattling.

 

I have some barely noticable resonance (radio off/windows up) when my truck passes through the 1500-1800 RPM range.

99silveradoz71 Senior Enthusiast

99silveradoz71

Posted
Posted

Well I'd say get your son a sailor's cap for when he rides up front, but that won't solve the problem. Sorry, was just in a good mood(despite the cough/sore throat) from listening to a little Cosby. I just laugh when we all try to describe some of the noises the vehicles make from time to time. I hope it gets worked out.

XTOAK Enthusiast

XTOAK

Posted
  • Author
Posted

I hear ya...I couldn't explain the sound until my wife said it sounded like blowing across the top of the bottle. It fit and I used it....

  • 2 years later...
mjwencl Enthusiast

mjwencl

Posted
Posted

I still have this issue with my 2004 Crewcab 2500 LD w/6.0L exhaust.

 

Anyone else find the problem. Dealer says they cut the system and install a flex tube to cure it. Doesn't sound like a fix to me. More like a band-aid.

 

Others experience this or find something that works?

OnyxMAX Enthusiast

OnyxMAX

Posted
Posted

are you shure it's exhaust and not the intake makeing the sound.

 

if it's in the exhaust i would say it's misalighned parts kinda like when you take 2 blades of grass and blow through them or paper and it vibrates and makes that sound. intake is also good for makeing them foghorn sounds.

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