Buzz after AAM Short Tail install

RonZwanson

So I installed some AAM Shorties just about two weeks ago now. I'm not sold on them yet, for a couple reasons. First of all, none of the videos on YouTube come close to accurately depicting how LOUD these things are. They don't sound bad, just LOUD. I don't know if I can live with it as much as I drive the thing.

My primary gripe is that there's a buzz/plasticy-sounding rattle coming from somewhere around the hatch. I'm wondering if anyone has experienced the same thing after installing new exhaust, particularly the Short Tails. I plan on doing some exploratory surgery whenever it stops being rainy and frigid, but that may not be for a couple more weeks. I noticed the tips of the exhaust basically sit right against the cutout in the bumper. And since the buzz sound is typically when I accelerate with some gusto, I guess that could be it, but based on the sound, I think it may be something in the hatch door.

Anybody have any feedback, or likely places I could search, before I go nuts tearing down my car? Anyone had a similar issue? Any feedback would be appreciated. I did search around, but didn't find anything specific to this. If anyone knows of a helpful thread I'll take that too.

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Hotrodz

Did you remove the heat shield on the rear right side???

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NickTurnon

Generally depending on how cold or hot it is in the day, the back hatch rattles and vibrates. Not only that but you can't really put your finger on where its coming from.

The only real way to get rid of it is some dyna-mat or something comparable-

Mine rattles hardcore around certain RPMs as well. 3500-5k

Thats just something you gotta live with if you want to be LOUD

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FairladyZ

It's either your license plate or the heat shield.

NickTurnon

****CHECK HEAT SHIELD FIRST

If thats not it, its something near your spare tire, or your trunk light, or your plastic components, or your wires....

Could be anything.

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jcosta79

Hmmmmmm... Let's see... If I get rid of all my mufflers, will my car be loud?

Probably not.

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kenchan

op- chances are the tips are rubbing your bumper. just get some small washers and lower the entire hanger bracket for the muffler section.

i had to do this too to even out the clearance of my fujimura muffler (also rear section only). if you're willing to pay the price the 2 short tails with cans, fujimura sounds fantastic. the reasons why i did not go with the full catback is

1) fujimura sounds good. not super deep
2) nice appearance and plenty of ground clearance.
3) convenience easy to install and remove if needed.
4) weight reduction and performance gain (per manufacturer).
5) price. it's like <1/2 the price of a full catback (650 or something paid).

GL!

Japanjay

I got shorty tails and have been dealing with the same issue. I am pretty sure there is a ever so slight buzz from the heat shield, but the major buzz I bet you are getting are from the tie down rings in the trunk that are on the outside of the plastic. Try standing them up right so the rings are not touching the plastic and see if the major buzz goes away, then if there is a buzz left, but much more quiter then that is the heat shield. The irony in the fact I have been dealing with this for a while now and trying to tracak the major buzz down and about 30 mins ago I tried standing the rings upright just out of curiousity and sure enough it stop the major plasticy buzz. I have torn my trunk apart like 3 times trying to find where is was coming from. LOL.

USMCASA

^doesn't the install instructions say remove the heat shield?

from aam's website: Please Note: To fit the S-LINE Short Tail Exhaust properly requires removal of emissions canister shield.

RonZwanson

Thanks to everyone who replied. Got a lot more info than I actually expected!

Everyone can rest assured, I definitely took off the heat shield when I installed them.

A lot of good ideas here. I may have thought of the license plate some day years from now, when I have a different car, but I would probably never have thought about the tie-down loops. Good thinkin'. I'll check all this stuff out, maybe over the weekend. And I'll be sure to search for "what mufflers do" on Wikipedia. I had no idea...

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Sales@AAMComp

OP,

For the tip that's rubbing the bumper or coming extremely close, try loosening the nuts back by the intermediate pipe side, and move it around before tightening it down. We had a local customer that had "fitment" issues too, we told him to bring it to the shop thinking it may be a production/manufacturing issue but it was technically "installed" wrong. A little movement on that end makes a huge difference on the tip side

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RonZwanson

Thanks! I'll definitely check that out.

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Schsplayer00

Thank god Im not the only one, I have the AAM short tails as well i did have the dealer take off the heat shield as instructed to, so the sound is not from that. I have narrowed it down to the plastic around the hatch window. Just like you it only happens when accelerating fast around 3500 to 4000 rpms, then again it only does it sometimes usually if i tap on it one good time it stops. When the plastic vibration sound is not there i think they sound amazing I love them inside sound and most def. the outside sound its way meaner and deeper than most of the other Z's around here with other exhausts. The plastic vibration is my only issue and i would really love to find a solution to it then it would be perfect. If you figure anything out let me know and i will do the same.

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Schsplayer00

Oh and my tips ended up being just right as far as the distance from the bumper they look like should IMO, i have the burnt titanium tips though not sure if they are different from yours.


I will check the tie down rings in the morning i didnt think of that but it does sound like the vibration is higher up than the tie rings but hey maybe we will get lucky and that will be the culprit.

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09 White/black Touring/Sport<HKS true dual exhaust burnt tips, Stillen G3 intakes, Berk test pipes, Motordyne intake manifold, Motordyne thermostat, Stillen under pulley, Uprev tune.

XwChriswX

I don't have the AAM Short Tails, but I believe I have the same Rattle IN the hatch as the OP.

I've torn apart my hatch interior multiple times as well trying to figure out what it is. So far I have narrowed it down to the 3rd brake light. It has 2 posts that stick out to align it when you're putting it into the hatch. These posts go through small alignment holes inside the hatch. If it isn't centered (which they never are) they will vibrate as the exhaust goes through the 2-3k resonance band. Major aggravation ensues.

So far I have installed rubber grommets in the holes to center the posts and prevent them from moving. So far this has prevented the "metallic" sound, but the posts still vibrate. So on to step 2. I have purchased some dense foam that I will try to stick on o the hatch interior trim, and when reinstalling, should brace the posts and prevent their movement, or at least muffle it to when you can't hear them anymore.

I'll be doing this over this weekend so I'll make sure I take video and pictures to help the rest out if it works...

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