Muffler Rattling... fixable?

**Naaman** · 08-24-2012, 11:53 AM

So, I've recently developed a rattling sound in my muffler. It's a very tin-ish sound that happens mostly on initial acceleration. When I've had the car on a lift, I've tapped on the muffler and the sound seems to be originating inside.

It's a stainless steel, Magnaflow, for what that's worth. Is my muffler all "rotted" away inside?

**35th-ANV-SS** · 08-24-2012, 05:40 PM

I would say it is starting to break down inside.

**SuperSSguy** · 08-25-2012, 12:40 AM

Originally Posted by Naaman

So, I've recently developed a rattling sound in my muffler. It's a very tin-ish sound that happens mostly on initial acceleration. When I've had the car on a lift, I've tapped on the muffler and the sound seems to be originating inside.

It's a stainless steel, Magnaflow, for what that's worth. Is my muffler all "rotted" away inside?

Originally Posted by 35th-ANV-SS

I would say it is starting to break down inside.

If it is Magnaflow has a warranty..do you still have papers for it? How many miles and how old is it? Cause the ss piping is lifetime warranted but im not sure the muffler would be?..

**Naaman** · 08-25-2012, 07:17 PM

Unfortunately, I'm not the original purchaser, so the warranty would not apply to me. But I looked up some prices, and the mufflers are less than $150, so it shouldn't be too much of a financial hardship. But I did notice that there is no weep hole in the muffler. Is that typical? Or is the weep hole an "OEM" thing that aftermarket manufacturers don't bother with?

**SuperSSguy** · 08-25-2012, 10:43 PM

Originally Posted by Naaman

Unfortunately, I'm not the original purchaser, so the warranty would not apply to me. But I looked up some prices, and the mufflers are less than $150, so it shouldn't be too much of a financial hardship. But I did notice that there is no weep hole in the muffler. Is that typical? Or is the weep hole an "OEM" thing that aftermarket manufacturers don't bother with?

Oh crap... you know off hand i cant remember..Ill see if i can get a peek at it tomorrow? As far a the muffler goes im not sure which muffler you have but with mine its basically a flow through design..not any baffles in the way of the exhaust.but that still doesnt mean it didnt take a dump on ya!..................oh and by the way im likin your vert maro!! sweet lookin,dont see too many and the interior being light as opposed to black makes it more unique...Nice!

**pajeff02** · 08-26-2012, 04:37 AM

I do not believe my Magnaflow has a weep hole. All the water in the system runs out of the joints that are band clamped.

**Naaman** · 08-26-2012, 05:00 AM

Originally Posted by SuperSSguy

Oh crap... you know off hand i cant remember..Ill see if i can get a peek at it tomorrow? As far a the muffler goes im not sure which muffler you have but with mine its basically a flow through design..not any baffles in the way of the exhaust.but that still doesnt mean it didnt take a dump on ya!..................oh and by the way im likin your vert maro!! sweet lookin,dont see too many and the interior being light as opposed to black makes it more unique...Nice!

Why thank you. I used to hate the color, but when she's all waxed and washed, the color is just so rich and deep.. and the metallic flecks really add something that a flat color just can't compete with.

As for the muffler, I think I'll just order a new one. The old one is cracked at one of the welds, anyway... which may be how moisture is getting in.

**pajeff02** · 08-26-2012, 08:32 AM

Water is a byproduct of the combustion process -- short tripping the vehicle is what kills an exhaust. Once the system comes up to temperature, the moisture remains within the gases and is expelled out the tailpipe rather than condensing on the cooler metal inside the piping and muffler.

**Naaman** · 08-26-2012, 10:11 AM

So to keep it fresh, I should let it idle for a while after short trip? Incidently, I take two very short trips every day...

**pajeff02** · 08-26-2012, 01:31 PM

Once a week, take it for a decent spin of at least 20 minutes is all your really need to do. I short trip it to work (2 mile drive), but usually end up going around 25 miles every other day or so with my DD.

**Firebirdjones** · 08-26-2012, 03:37 PM

Originally Posted by Naaman

But I did notice that there is no weep hole in the muffler. Is that typical? Or is the weep hole an "OEM" thing that aftermarket manufacturers don't bother with?

Some of your aftermarket mufflers still come with weep holes. I know certain models of the flowmasters did.

I usually add them myself if I feel the need. I just use an 1/8" bit and drill a hole on either end of a transverse muffler. You can even add weep holes to the pipes, generally right where they bend up to go over the axle is a good place.

Like Jeff said though, if you band clamp the system together you might have places where water escapes anyway so it's not necessary.

**Naaman** · 08-27-2012, 07:34 AM

Well it is band clamped on there. I guess I will just have to do some driving every weekend. Not a problem when the car is fun to drive.

**SuperSSguy** · 08-27-2012, 07:48 PM

Originally Posted by pajeff02

I do not believe my Magnaflow has a weep hole. All the water in the system runs out of the joints that are band clamped.

Agree the only place ive seen a little condensation drip was from there and the tail pipes. I believe thats a good sign showing a tight engine (healthy).

**SuperSSguy** · 08-27-2012, 07:53 PM

Originally Posted by Naaman

Well it is band clamped on there. I guess I will just have to do some driving every weekend. Not a problem when the car is fun to drive.

Big time agree with ^^..short trips are not good for your car...take her out on a good long drive.heat that puppy up and get all the moisture and carbon build up off her...also get your foot into it here and there clean that throttle body out by way of lead foot.....

**Too Fast** · 08-28-2012, 02:27 AM

^^^yes all the above. Short trips are the very definition of severe duty use, most people think severe duty is only for police/taxi, not true at all. If you mostly drive your car about 6 miles or less per cold start, that is severe duty. It takes that long for all the fluids to be up to temp. Idling a car is almost as bad, so don't do that!

I've done the 1/8'' drill bit thing in low spots on a couple of my cars exhaust also, to let the water out. Most exhaust rots from the inside out. I also had a baffle get loose on the muffler on my WS6, it was nasty. Fixed it with an Aerochamber. Lots of people love that Magnaflow as well!