Exhaust rattle= weights for the muffler?

[HyPer-50]

Alright, I've been having some pretty bad exhaust rattle for a while now, it's whenever I'm decelerating, and at high rpm, for instance, when I down shift to 3rd comin' up to a light. It's pretty obvious that it's the mufflers bangin' something, cause it sounds like some lil troll is under my car playin' bongo on my mufflers. Anyways, my friend goes to car tech school and his teacher told him somethin' about putting weights on the exhaust to dampen the movement. Anyone ever heard of this? or have any other suggestions? Thanks much.

 

[whtpny]

Dunno about the weight thing. I had an 01 GT that I put MAC catted H pipe on and the cats gave out and started to rattle inside and sounded like what you are describing. Put the car up on ramps or jack stands and idle it and do the screwdriver trick and see where it is coming from. Your sig doesn't stae if you have cats. Other thing too is to check that your pipes aren't touching the back part of your subframe at the rear. That will drive you nuts until you find it.

 

[HyPer-50]

Nahh, I got an off road h-pipe. I took my car to the local mustang shop, and they put it in the air, and tried to see any clearance area's, and they bent the pipes down some. It looks clear, but the muffler is definatly hitting something... Or atleast I'm pretty sure it is... Nothing else would be making a hollow tin can banging sound would it?

 

[whtpny]

Are all the hangers in good shape? I haven't heard of those mufflers blowing baffle plates inside at all either. Doesn't this little stuff just irritate the heck out of you. Did you guys run it while it was up in th air?

 

[strtracer442]

Check your trans mount, maybe your drive shaft is moving around on decell and catching the exhaust,also make sure your exhaust hangers are solid enough to keep the exhaust from moving/bouncing around.

 

[HyPer-50]

Are all the hangers in good shape? I haven't heard of those mufflers blowing baffle plates inside at all either. Doesn't this little stuff just irritate the heck out of you. Did you guys run it while it was up in th air?

Ya, both hangers are brand new. I just replaced the right muffler a few months back, because the local shop said it sounded like the baffle may of been broken in that one. and the left muffler got caught on a scissor jack at work so that one was replaced last month. And nah, we didn't run the car in the air.

Check your trans mount, maybe your drive shaft is moving around on decell and catching the exhaust,also make sure your exhaust hangers are solid enough to keep the exhaust from moving/bouncing around.

Well, I've got a driveshaft loop, so I dont think the driveshaft would be hittin' the exhaust. But that is almost what it sounds like. A really fast banging sound.

 

[Daggar]

I'm with ya Hyper... I've got a similar problem. The left side of my cat-back where it goes over the axle taps against the frame. Drove me freaking nuts. If you can find exactly where it's hitting you may be able to solve it just by looseing the nuts and rotating mufflers etc. until they don't hit then tighten them back up. I ended up using a little adhesive spray and heat resistive material that I got from home depot and stuck up the frame. I tried the roatation thing myself and it worked for a time but on the left side of my car... when I rotate one way it hits the frame over the axle... when I rotate it the other it hits the gas tank. So I ended up insulating it. Either way... it's not too hard to insulate it.

 

[2000xp8]

All these reasons are why i suggest to everyone to get bassani or magnaflow catbacks.

I've had issues with my flowmaster kits hitting in everyplace possible.
including, muffler agaisnt the frame (that's the worst by far), tailpipes hitting the upper control arms, and tailpipes hitting the gas tank. The cheaper kits have a poor design. I even put all new for hanger bushings on, it still hits the gas tank over bumps.

Over the winter i'm putting one of the 2 exhaust systems on that i mentioned above. The design is better by the gas tank, instead of going towards the back of the car at a 45 degree angle by the front corners of the gas tank, these kits have more like a 90 degree going around it.

The only possible way to fix your problem is to loosen the bolts that connect the h pipe to the catback, and have a friend twist the entire section on that side of the catback, and you retighen them in the new position.

 

[GRGT1994]

I had the hollow tin can sound, and it was my heat shields on my stock cats. The mounting corners had rusted out an come loose, leaving only one holding em in. The rest of the heat shield was left to vibrate and act like a cheap drum.

It can be hard to find these kinds of problems, because you can't quite recreate the bumps and vibrations that your exhaust goes through as you drive down the road. Just keep looking till you find the culprit.