Muffler making noise

[nola504boy]

Don't know if this is tech or should be in pictures & videos so if it needs to be moved feel free.

Anyway my muffler is making a rattle sound like it's loose. The thing is the bolts are tight. Can it be the axle back itself is bad? look at the video around the 32 second mark and the 2.20 mark you can really hear it. If I push down hard it stop but all the bolts are tight. BTW excuse the nitrous purge I didn't make the video for the muffler sound I'm just using this video to get some advise.

 

[J.Kidd]

I think you need to crawl under there and take a look to see if the exhaust is hitting any other part of the car. I don't think its a matter of any of the connectors being loose, it sounds like it is rubbing/vibrating off of something in the undercarriage.

 

[cbracoupe]

Odd sound. Are you sure it's not the mid pipe touching something? Only reason I ask is if the muffler is tight and you put pressure on it the noise stops. Those are non chambered mufflers correct?

 

[skwerl]

Most likely you've blown out the baffle in one or both of your mufflers. I went through 3 sets of stock Bullitt mufflers before finally going with the Borla. With 10 lbs of boost it was blowing out the mufflers in 4-5 months.

 

[mustangtcs]

This is why you have to do preventive maintenance. You see this guy checked them to late. The first sign of this was the bearings were burnt. Burnt bearings attract fish. If there's a fish in there you should just replace them or else they will just blow right out when greased like in the video at 2:20. Now these bearings do cost $800 for two, $100 for the third, and the fourth comes free. So do yourselves a favor and check them before this happens to you.

 

[AnotherS197GT]

Check the exhaust hangers. Sometimes after I swapped axle backs, my hangers would be too close to the rear bumper support. Then when the exhaust would get hot, it would expand enough to make contact and start rattling. I would crawl under the car and double check that nothing is touching, or close to touching.

If thats not it, see if you can determine which side its coming from, pop the muffler off, and shake it. That should tell you pretty quick if its bad. Or hit the muffler itself. I had a GTA that had a broken baffle or something, and I could smack it with my hand on the casing and it would buzz.

 

[01yellerCobra]

What's the minimum distance the hangers should be from anything? I have Borla Stingers and get a buzzing around 1800-2000rpm. It reminds me of a license plate rattle. Nothing is touching, but I've only checked when it's cool. And I have about a fingers clearance around everything.

 

[nola504boy]

Thanks guys, for the quick response. The hangers themselves are tight but I can't get under the rest of the car. With the sportline springs my car is so damn low to the ground I can't even see under the middle of the car. I need a new jack the kind for lowered cars.

It just seems weird that when I apply pressure the noise stops & the bolts on the hangers are tight. Also the mufflers are pypes violator's if that matters any. I think it might be ruined. I've heard you should run straight through mufflers with forced induction is this true? Because I'm using nitrous could that have ruined the muffler?

 

[skwerl]

You're going to have to shake the muffler and listen for loose pieces inside. This will most likely involve removing the muffler to check. Also, about 37 threads on floor jacks here and about 50% of the forum uses the cheap Harbor Freight aluminum low profile racing jack. Or drive your car up on a couple 2x6 or 2x8 pieces of lumber for a little extra jack clearance.

 

[nola504boy]

Most likely you've blown out the baffle in one or both of your mufflers. I went through 3 sets of stock Bullitt mufflers before finally going with the Borla. With 10 lbs of boost it was blowing out the mufflers in 4-5 months.

So I'm guessing you shouldn't use chambered mufflers with forced induction

 

[nola504boy]

You're going to have to shake the muffler and listen for loose pieces inside. This will most likely involve removing the muffler to check. Also, about 37 threads on floor jacks here and about 50% of the forum uses the cheap Harbor Freight aluminum low profile racing jack. Or drive your car up on a couple 2x6 or 2x8 pieces of lumber for a little extra jack clearance.

I'll check it out thanks. Lowered with a chin spoiler makes it hard to even put my car on racks at most shops. It wasn't too bad being lowered at first but once i added the spoiler smh.

 

[Captainstr8edge]

I don't know if this is your problem but mine rattle at idle sometimes because its hitting the panhard brace. Basically the actual part that goes up over the axle is kinda resting on there. I am going to need a lift to adjust mine properly because its the mid mounted mufflers that need to be adjusted but yours might just need the hangers adjusted.

 

[Drewskie]

Cant hear the video at work but mine used to rattle when the RPMs were right, as stated above. It was only the tip hitting the bumper. Maybe check the alignment of the muffler?

 

[nola504boy]

I don't know if this is your problem but mine rattle at idle sometimes because its hitting the panhard brace. Basically the actual part that goes up over the axle is kinda resting on there. I am going to need a lift to adjust mine properly because its the mid mounted mufflers that need to be adjusted but yours might just need the hangers adjusted.

To be honest I think the hotrod cams are shaking my car apart. And that's not in a good way.

 

[Captainstr8edge]

To be honest I think the hotrod cams are shaking my car apart. And that's not in a good way.

up the idle a little then

 

[fdjizm]

I have a mid pipe that is doing this, something in the inside is broken.
Going to replace it soon, but I'll bet something is broken on the inside.

 

[nola504boy]

I have a mid pipe that is doing this, something in the inside is broken.
Going to replace it soon, but I'll bet something is broken on the inside.

Yeah its the mufflers. Today I floored (wot) my car and the mufflers sounds like something is broken on the inside. Just sick of putting money into this car. Think it's time for a coyote

 

[302GT]

Maybe yours has failed similar to this one...

 

[LAStang1234]

Thanks guys, for the quick response. The hangers themselves are tight but I can't get under the rest of the car. With the sportline springs my car is so damn low to the ground I can't even see under the middle of the car. I need a new jack the kind for lowered cars.

Wheel ramps would help out in this situation!