Chevy Trailblazer SS Forum banner

SW LMF Question/Concern

1274 Views 10 Replies 5 Participants Last post by  Blades
I just installed my LMF catback the other day and it's loud but nearly as loud as I was expecting. Although I had a flowmaster 40 series in place of the stock muffler and I removed the resonator and I'm sure that would explain why it's not much louder to me.

Anyways, I don't know if it's supposed to sound like this or not but during wot and sometime crusing around at 2.5k - 3k rpms it echoes really strongly. It's a hard sound to describe but I just wanted to make sure that it was supposed to sound that way.
1 - 4 of 11 Posts
It may not be what others are talking about.. It might be the muffler vibrating at a very high hz.. Meaning.. very fast and short travel. Replicate the sound in park.. Take a towel or glove and place some force onto the muffler to "stabilize" it.. My truck seemed to start this sound at 2100rpm.. I had a friend hold it at that rpm.

Does it kinda sound like blowing across the top of an empty beer bottle? What I did was take 3 hose clamps and bent them to the size of the muffler.. Wrapped em around so that they hugged the muffler.. Wedged some small paper towel fragments between the spots where the adjustment screws for the clamps were.. No more weird bellowing echo. Kinda ghetto on paper but it worked out nicely.

The muffler is just too big.. It needs more structural stabilization esp in the middle.

:rofl: that's EXACTLY what it sounds like! I'll have to try that out and see if that helps.
:rofl: that's EXACTLY what it sounds like! I'll have to try that out and see if that helps.
I'm going to try that tomorrow to see if it helps, but it pisses me off to ghetto rig a brand new catback!!
What your hearing is DRONE. Very trypical with straight-through style mufflers. What it is resonance from inside your muffler just a pitch higher in frequency than the resonance leaving your tailpipe. Thats when you get that low bass-sounding rumble..
It's definately not drone. My previous setup was a small 40 series Flowmaster without the resonator :eek: and I used to drive an RSX with a Greddy catback :rolleyes:, so I definately know what drone sounds like! I actually put a couple of pipe clamps around the muffler pretty tight like Blades did and that seems to have gotten rid of about 90% of the noise I was hearing. It does drone a little bit though, but I don't mind it at all.
1 - 4 of 11 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.