Ok, I have a Dynomax Super Turbo Muffler, and when its cold, its rattles REALLY bad. It also seems to rattle at exactly 1800RPMS, and whenever I rev it up, when the RPMs drop it rattles, and no time before or after. Just when its cold and at that RPMs, or after revving. Is something loose, or am I going to have to replace the muffler. Its not really all that bad, but just annoying I guess. I am hoping its something I can just fix. Thanks!

 

Bearings. Def the muffler bearings dude.

In all seriousness, without hearing it first hand, I'd be guessing. Crawl under and see if you can spot anything that might be loose. Maybe take it to a muffler shop and have them look it over.

 

i had the same problem and all that was wrong was some heat guards were loose

 

I have a similar problem. I've only had my flowmaster exhaust installed for about 3 weeks and now its starting to rattle a bit. Well thats what I thought it was but now I believe it may be a heat guard coming loose. Do you just tighten the heat guards back up or do you have to have them welded back? I'm gonna crawl under the car tomorrow and take a look.

 

just tighten them back up, in fact, mine just started to rattle, so this weekend im going to tighten them up when the car is on the ramps when i change the oil. check the one on the intermediate pipe too. that one gives me the most problems.

 

i had mine welded to make sure its not goin to happen every month, seems to be a common problem with flowmaster