I have an 03 400i automatic that has developed an annoying vibration from the exhaust with only 50 miles on it. The noise is front the left side and towards the front. I thought it was the stainless heat shield but i tightened it, didn't work, so I removed it entirely, and the noise is still there.

It is worst when the machine is cold, and goes away when totally hot, probably because of expansion. I tightened the front exhaust bolts, but don't know how much torque to give it. Also tightened the rear bolts and muffler, but I am sure the noise is more from the side and front.

Please help. A friend has an 02 375 that doesn't do this noise. The dealer said it was normal. Not.

 

I have the same bike and also have the same vibration/noise. Mostly at low speeds, when I go past ...........20 the noise go's away but very bothersome when at low speeds. I too would like to locate the problem. Mine seems to be coming from the front aslo, I am not sure if it is the muffler? [img]i/expressions/face-icon-small-confused.gif[/img]

 

Try putting your foot against the exhaust on the left side when you hear the noise. Mine stops when I do this because my shoe cushions it. Mine is worst at about 1/4 throttle, and in low gear because the rpm's go higher at slow speeds I guess. Could the muffler cause vibrations that travels up the pipe and is heard further up?

 

I have a 1999 500 with a little over 7000 miles on her. At about 4000 miles or so the muffler developed a vary loud Vibration. What the vibration noise turned out to be was a baffle inside the muffler broke lose and would rattle around. My solution was to get a BFH (big @#%& hammer) and bash the hell out of it until it went a way. Another words I dented the muffler until the lose baffle got wedged agents the dent. Aside from replacing the muffler or cutting it open then welding it back up, that was the only way I could stop the noise. This might or might not be the cause of your problem but you might want to look into it.

 

my wife's 03 400I auto has had the same trouble since we bought it last month. The dealer took off the heat sheild and put washers under the bolts holding it on. It used to vibrate all the time-after their "fix" it just does it at 12-15 and at 20-23 mph. The dealer is still looking for a fix as I write this. I could put my foot on the heat sheid and it would dampen it but not stop it. The bolts were tight and it still did it. If anyone finds a fix let us know. Sounds like AC needs find the fix and send a service bulletin to their dealers. It sounds like the dang things going to blow up.

 

some of these dealers are just idiots. are we suppose to believe this crap. yeah, its suppose to rattle, all the focus groups preferred the rattling - come on. check to see if the little nuts that the heat shield bolts screw into have not come loose. i think their just tack welded on. also, check the header bolts. if you dont find where the noise is coming from, call AC corporate, that will do wonders.

 

To fix the problem put one or two washers between the rear exhaust mount. You will have to remove the bolt holding the exhaust to the mount and slide the washers in between the mount and the exhaust. Make sure the washers are about .150 thick. Mine has washers about .112 thick and this cured the problem completely.

 

I had the same problem with a 400 and what i did was put a flat washer and a rubber washer between the mount and the frame(very simple fix, I cant believe the exhaust is solid mounted)

 

Between the exhaust mount and the frame? And this may be a stupid question, but don't you need to be concerned about the rubber washer melting? Or is it not hot there-I can't look as her machine is still at the dealer. Thanks for the fix, if the dealer can't fix it I'll suggest yor fix and look like I know alot more than I really do!! Thanks

 

yes, the mount just in front of the muffler. and as far as getting hot, just make sure you have the rubber washer against the frame, then the flat washer next to the exhaust pipe. the guy i fixed it for hasn't said that it has melted.