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Rattling muffler

bigalpha

bigalpha

Moderator
Location
Tucson, AZ
I took 'er to a muffler shop because it sounds like one of the hangars broke loose, causing the muffler to vibrate against teh body.

Not the case. Something inside the muffler itself is vibrating/rattling when the Jeep is on.

Moving the muffler during use causes no change in the vib/rattle. I cannot create the vib/rattle w/o the Jeep running. The vib/rattle gets quicker when the engine is revved.

My question is: can the internals of a muffler be fixed, or is it more cost-effective to buy a new/used muffler?
 
This is a no brainer, replace the muffler. Are you sure it's the muffler? Your description sounds like the noise the cat makes when it goes bad[converter, not pussy].If it's the muffler buy NEW,not used. mufflers are cheap.
 
cherokee chuck said:
This is a no brainer, replace the muffler. Are you sure it's the muffler? Your description sounds like the noise the cat makes when it goes bad[converter, not pussy].If it's the muffler buy NEW,not used. mufflers are cheap.
Click to expand...

Yes, I'm pretty sure it's the muffler. There is nothing else down there for it to rattle on. It's not touching anything, and the sound is coming from the muffler.

I just wanted to check to make sure replacing the muffler was the way to go, not something else.
 
The cat is right before the muffler, that is most likely what is rattling because cats go bad. Never heard of a muffler going back and rattling around, unless the catalyst from the cat blew into the muffler and was rattling around in both devices.
 
Blaine B. said:
The cat is right before the muffler, that is most likely what is rattling because cats go bad. Never heard of a muffler going back and rattling around, unless the catalyst from the cat blew into the muffler and was rattling around in both devices.
Click to expand...
2X When we did my sons' exhaust recently the muffler was full of honeycomb from the cat. Turbo mufflers will rattle when the baffles break loose but usually mufflers don't rattle, they blow out.
 
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Blaine B. said:
The cat is right before the muffler, that is most likely what is rattling because cats go bad. Never heard of a muffler going back and rattling around, unless the catalyst from the cat blew into the muffler and was rattling around in both devices.
Click to expand...


I'm pretty certain it's the muffler, and not the cat.

I'll check again today and make sure I'm hearing things right.

I thought maybe one of the baffles inside the muffler broke loose or seomthing and is rattling around.
 
Yea, could be the muffler I suppose, but a classic symptom of the catalytic going bad is a "rattle". Just curious as to how you are sure it's the muffler making the noise? Noises are notoriously difficult to isolate. My money is on the cat. Exhaust hardware is pretty much always replaced with new components for obvious reasons..... Good Luck!
 
Let's assume the Cat has gone bad, and it's not the muffler.

Will the cat rattle even if the Jeep is not running?
 
If you can move it enough it will. I have seen/heard a muffler or two w/ loose internal parts(my bro currently has something loose inside his magnaflow resonator).
 
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Could be the muffler bearings.

Sorry had to :laugh:. If it's a 96 the cat would go bad and blow broken brick into the muffler. Suggest checking with your stealership first.
 
Smack the bottom of the cat and the muffler with your hand(when they are cold obviously) and listen for anything...
 
If it's the original muffler, that is not usually the first sign of a bad muffler, they were pretty tough.

However, cheap aftermarket mufflers die all the time. My 2.5L Wrangler and my Cherokee have each eaten a couple. The baffles are just stamped and pressed into place, and they break loose and rattle at idle. I know it was the muffler because I disected it, and pieces of the baffles fell out.

Could it be a shot Cat throwing off pieces? Sure. That's why I tell people to run a muffler and not a glass pack ;)

However, I doubt the Cat will be covered by warranty anyway, not from a 96'.

Once you remove the muffler, you can inspect the Cat with a flashlight. If the honneycomb appears damaged, replace it. Be sure not to hollow it out, but replace it and take the old one to the scrap yard. Some of those fetch a good penny, or atleast will pay for the gas to take it there.
 
Soooooo...what did the "muffler" shop say.

I would think a guy that deals with this all the time might have a better answer than "yep, yer mufflers rattlin' around, better replace it".

I'd second or third the cat...or the other theory that the wasted cat blew some crap INto the muffler. Unless you can manually move the muffler around and reproduce the rattle, then it's internal!

^ ^
(- -) CAT
(*)
 
Jeepm@n said:
Could be the muffler bearings.

Sorry had to :laugh:. If it's a 96 the cat would go bad and blow broken brick into the muffler. Suggest checking with your stealership first.
Click to expand...

The muffler shop charged me $50 to replace the exhaust fluid :dunno:

I'll try banging the muffler around after work. I didn't get a chance to fool with it last night. The rattling is definitely from the muffler, while the cat hardly makes any noise at all.

If the cat doesn't rattle when I shake it around, are there any other ways to check it w/o taking off the muffler?

The muffler guy didn't tell me "yep, yer mufflers rattlin' around, better replace it". I had merely asked him to check and see if any of the hangers were broken loose or anything. They are my trusted muffler shop; I've taken 3 cars there, and each time, they fixed it great.
 
try a rubber mallet...it will be a "sharper" blow and will allow you to get a better strike than your hand. that should be able to isolate the trouble maker for you. aside from the rattling do you have any other symptoms? loud exhaust, power loss, etc?
 
If the cat is bad, you can take it to the dealer and they'll replace it and reprogram the computer. E22 recall.
 
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