Rattling / Resonance from RR under light throttle

[SnowDrifter]

Took me a bit to realize this was coming from the hoe and not the construction site

Sound comes from RR area from the perspective of the drivers seat. Seems to be worse when cold, between non existant and barely noticeable when not (30+min drive time).

Happens at a very specific RPM ~1300, light throttle. Going slower or faster seems to alleviate the issue.

Checked catalytic converter trims, fuel trims, Neither of those show any issue w/ the cats or signs of obstruction. Noted no sound when struck with a hammer.

Checked heat shields were tight and not contacting.

Would I be correct in my takeaway that this is something internal with a muffler?

Little video. Apologies for the music in the background. This was a 'oh hey there's that noise' instead of a diagnostic drive

 

[drakon543]

try to get another video with any background noise you can eliminate. i cant hear anything particular that i can pinpoint as something that isnt background noise. as a side note with the truck parked and nothing is contacting might not be the case under load. as the exhaust is bolted straight to the engine as the engine flexes a bit under throttle can pull the exhaust closer to something. so on that note do you have any spots on the exhaust that are close to something but dont appear to be touching while it parked. they could be touching when your accelerating. other diagnostic options tp check to loose heat shields and spots where it could be touching. while the exhaust is cold you can stuff a shop rag under some heat shields and do a short jaunt around the block. dont go far as you dont want to get the exhaust too hot with those rags in there but it will add some cushion as a test.

 

[afpj]

Sounds like a buzzing noise right after you completed the turn, like an air compressor? Unless that was part of the song.

 

[SnowDrifter]

Sounds like a buzzing noise right after you completed the turn, like an air compressor? Unless that was part of the song.

Not part of the song. That's the noise

 

[iamdub]

Only does it under load? U-joints? Transmission? Rear end?

 

[Doubeleive]

get under it with a rubber mallet and start smacking stuff you might find it that way, that's how I found a loose heatshield on a cat, had the muffler shop tack it down, noise gone another one was a loose heatshield on the transmission, that one would only resonate at a certain rpm also.

 

[S33k3r]

Do you have an air ride suspension?

 

[SnowDrifter]

Yeesh..... Well it's definitely inside the muffler whatever it is.

Anyone make bolt-on replacements?

 

[iamdub]

Yeesh..... Well it's definitely inside the muffler whatever it is.

Anyone make bolt-on replacements?

That's much better than anything else it could've been.

They're ALL bolt-on with these!

 

[PNWYukon]

If you have the original muffler, check the heat shield on top of if. Mine made similar noise because the shield was torn from welds at both ends.

 

[SnowDrifter]

If you have the original muffler, check the heat shield on top of if. Mine made similar noise because the shield was torn from welds at both ends.

Will give it a check when the snow ***** off. I only did a quick crawl under the thing while in a parking lot with a cold fist. Missed that there was a heat shield on top. Hopefully that's it? Will check back in later

 

[Elmo]

For years I chased a rattle. Last week I found a quarter in the opening for the rear anchor of my second row driver side seat. About 1/3 of it was visible while I had the seat up to vacuum. The quarter apparently moved up and down the channel. So I just got lucky. Sometimes it sounded as if the rattle was in front. Sometimes it was alongside. Sometimes it was behind me. Sometimes the quarter got hung up and did not rattle at all. Sometimes it was speed sensitive.

 

[iamdub]

For years I chased a rattle. Last week I found a quarter in the opening for the rear anchor of my second row driver side seat. About 1/3 of it was visible while I had the seat up to vacuum. The quarter apparently moved up and down the channel. So I just got lucky. Sometimes it sounded as if the rattle was in front. Sometimes it was alongside. Sometimes it was behind me. Sometimes the quarter got hung up and did not rattle at all. Sometimes it was speed sensitive.

Hmm... That makes cents.

 

[Doubeleive]

I had one for a long time on a 4runner I don't know how many times I had it checked each time it went in for service or anytime it went up on a lift we could never find it, then one day I bumped into the front bumper apparently at just the right angle and it made the noise, turned out is was a loose mounting bolt for the bumper and it only wiggled one way otherwise it would appear tight. another one on a silverado was the heat shield around the motor it was bent just enough that it would touch on the exhaust manifold at a certain point took a while to find that one also just happened to notice it one day while looking at something else. things like that will drive you nuts and make you think there is something else wrong

 

[iamdub]

I had one for a long time on a 4runner I don't know how many times I had it checked each time it went in for service or anytime it went up on a lift we could never find it, then one day I bumped into the front bumper apparently at just the right angle and it made the noise, turned out is was a loose mounting bolt for the bumper and it only wiggled one way otherwise it would appear tight. another one on a silverado was the heat shield around the motor it was bent just enough that it would touch on the exhaust manifold at a certain point took a while to find that one also just happened to notice it one day while looking at something else. things like that will drive you nuts and make you think there is something else wrong

I saved $1,000 on Jenn's car cuz the dealer said it needed rear brakes. He said after driving for a few minutes, they start to make noises, probably from getting hot. It sounded nor acted anything like brakes. During the test drive, I mentioned how concerned I was that it had to be something seriously wrong (read: "expensive") with the brakes, and used that as bargaining leverage. On the way home, I stopped at a grocery store and pulled the bottom of the rear bumper cover out and straightened the bracket. Ten-second fix. The PO probably backed into a curb and pushed it inward. When the exhaust expanded from heat, it would lightly rub the bent bracket.

 

[SnowDrifter]

Got a chance to go under today.

Heatshield on top of the exhaust popped loose on the left-front corner. Just bent it up enough that it's not making contact any more. Probably should have welded it but the only 'welder' I have is an oxy torch and it's a bit too small under there for me to trust having that much waste heat under the car. Rattle's gone though! Back to driving like a Chevy and not a beat out honda

 

[PNWYukon]

Got a chance to go under today.

Heatshield on top of the exhaust popped loose on the left-front corner. Just bent it up enough that it's not making contact any more. Probably should have welded it but the only 'welder' I have is an oxy torch and it's a bit too small under there for me to trust having that much waste heat under the car. Rattle's gone though! Back to driving like a Chevy and not a beat out honda

You might get a humming bird sound from that heat shield once in a while depending on how loose it becomes. Sometimes when idling, but anytime is possible. I was able to wedge a nice rock into mine.

 

[Jimmyy]

A guy at work bought a Dodge car of some kind and it had a rattle. Bought in to the dealer a few times. Dealer was “unable to hear it”. He got to the point where he modified his exhaust to help cover the sound up. When he removed the muffler he found a box end wrench in the muffler.