Buzz after AAM Short Tail install
 

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. :tiphat:

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

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

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

****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.

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

Probably not.

:rofl2:

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. :tup: 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!

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.

^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.

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...

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

Thanks! I'll definitely check that out.:tup:

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.

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.

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. :mad:

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... :ugh2:

Nice keep us posted. I want this fixed it is driving me nuts!!!

I KNOW!!! OMGWTFBBQ!!! :mad:




:inoutroflpuke:

I'm getting new rear tires installed tomorrow, so I'll fool around with some of this stuff and let you guys know if I miraculously solve this while I'm driving to the shop.

Thanks again!

buzzing noise/rattle has been explored to death on this forum if you do some quick search there are a few DYI's to fix it, there are 2 places where it could be comming from, one is the latch for the hatch and one is behind the headliner, in both cases it sounds like it comming from the back because the sound travels down the windshield (that was my case)

its probably behind the headliner, next time you're dirving and you hear the noise put you head in the center of the headliner in the back and push and see if it stops, if it does than you found your source of rattle.

Explain this? Not really able to visualize anything based on that? :ugh2:

There is an electrical plug in the hatch that plugs in to what I guess is the 3rd brake light that is an extremely loose fitting.. That's one of the places I'm going to investigate today. But other then that, I'm not sure. :ugh2:

I know it isn't my headliner as I've never heard anything from that part of the car. :ugh2:

Its the heat shield, I had too many fights with mine, so I tore it to pieces.

I had a rattle with my non-res FI, i was sure that it was commign from the hatch but after insulating everything it the rattle was still there...eventually i found the rattle behind the headliner, the sound would travel down the windshield the bounce back so it sounded like it was the hatch but it wasn't. The only reason i mentioned latch is because i remember reading about it on some thread, some peeps moved the lock down a bit so that hatch closes tighter...

I dont know what could be rattling in the hatch because that is not where my problem was so i didn't have ot fix anything but others did, do some seraches and i'm sure you'll find all the threads on hatch rattling

Do you know what/where it is in the headliner, I'll check there today as well, just not sure what I'm looking for? :confused:

all you have to do is press on the hump part of the headliner hear the rear window, im my case there are plastic push pins that are holding the headliner up, i had to put some tape on them because they were rattling against the metal roof. See the link, towards the bottom there is a pic of the plastic push pin that has a suqare base that is against the metal roof, that will rattle and drive you nuts.

http://www.the370z.com/exterior-inte...ar-area-2.html

From the Journal entry:

I don't have a Touring, so I don't think my problem is the wire in the headliner. :ugh2:

But I do think I need to invest in some Dynamat. :icon17:

^i don't have a touring, i have a base w/sport pkg, and i DO have that buzzing sound coming from the headliner where it meets with the hatch.

I just went around trying to do something else, and it does Not sound like it's coming from the headliner area. I even pushed on it to see if the clips were loose and it's pretty snug up there... :ugh2:

you have to do this while you're driving and you're hearing the buz, just felling it around itsn't gona do anything.

I was, that's what I meant.

ok, then its somewhere else....you should read that entire thread, different peeps have different rattles...some suggest putting a penny in those holes where the rubber stumps go from your hatch to tighten it

I am 98% sure it's the electrical plug to the 3rd brake light. That thing is not tightened down at all, and it's between the two metal panels of the inner and outer body of the hatch, so you can't get to it to tighten it down. That's where my foam idea is coming in.

Hmm looks like I have a decent amount of things to try, mine is the touring/sport so thurs I'm gonna get up early and start one by one trying to isolate my rattle. Where can I get the dynomat stuff or whatever it's called?

To anyone interested, a weird thing happened yesterday morning. As I was taking my car in to get my two rear tires changed, I did the head liner check on the way in. In my case, the headliner wasn't the culprit.

The weird part is that after I replaced my rear tires the buzz was nearly gone! :ughdance: The tires that were on there previously were stock RE050As, but whoever had the car before me sprung for the run-flats. My right rear tire was WAY low, like, 1/32 low. Since the buzz seemed to come from the rear right, I wonder if the harmonic resonance of the tire caused it at certain tire rpms, especially since the run-flats have such stiff sidewalls. My new tires are not run-flats, so softer sidewalls (and holy Moses, what a difference in ride comfort).

My drive home was in a bit of traffic, so I couldn't really give it a full test. I'll keep researching over the next couple days.

Any thoughts? Any similar experiences?

How big of tires did you go in the rear?

Also, I have the same issue as you and even with 275's on the base 18"s- I can still hear vibrations. It is reduced though, like you mentioned.

If you have the time, call GTM Mat and order their sample of material and do your trunk. That might help a ton..

If I decide to buy their midpipe, im definitely going to have to mat my trunk

I have the stock sport package size tires. (275/35/19) They're a different tire though than stock. They're Potenzas, but they're the S04 Pole Positions.

I drove around briefly yesterday on my way to work, and the buzz was still basically gone. It only happened when I really got on it once, which I can probably deal with since I don't do that a whole lot.

However, in another fun turn of events, I drove around BRIEFLY because when I got back in my car after stopping for lunch, STEERING LOCK. I knew I shouldn't have been putting that off like I have...:shakes head: So the Z's at Nissan. Thank god I bought an extended warranty. It's left me stranded twice in 6 months. (Last time was clutch cylinder crapping out.)

I did put some generic matting in the trunk about a year ago when I put in my subwoofer, but I did an admittedly crappy job. It was cold, and I was short on time and patience, so I kinda half-assed it. I should probably go back and do a better job.

Oh, and I see you have plastidip in your signature. What did you use it on? I'm planning to gloss-blackify my wheels because the coating on them is flaking off. (another aggravation) Did you get the results you were looking for?

How hard was it to remove the panels? I want to do this soon..

I went to get gas las friday because the car had about 40 miles til empty. I get back in the car after filling up and my brake wont go down. Push button didnt work. Car wouldnt do anything. STEERING LOCK. Had to have it towed to Nissan which cost $78 and then $100 deductible. I guess it was better then the $1300 they wrote on the invoice.

This might help. I made this video awhile ago before I vinvyl wrapped my roof and redid the headlights a lighter shade of dip

Nissan 370z Plasti-Dip Blackout Tailights & More - YouTube

got mine installed on sunday. no buzzing for me :happydance:

Well la-di-frickin' da for you! :gtfo2: Ha. Just kidding. Seriously though, good for you, because it's so agitating. It's one of those things you may never solve if you've got it... Hopefully mine continues to be a relatively dead issue. Do you like 'em so far?

The trunk panels weren't that tough, just tedious, like any other interior stuff. There's a lot more junk in that trunk than I thought there would be. If I remember correctly, which I probably don't, I think there was really three big plastic pieces. One around the back of the hatch (near the latch), and the two sides coming up over the wheel wells. I also found part the previous owner's mic stand in there, buried under the spare. Bet the dude looked for that for quite a while... You just have to go through a bunch of pop rivets. Be careful when you take off the rubber liner around the hatch. Make a mark on it for when you replace it, so you know how to line it up. It's just a big rubber ring, but it kinda forms to the shape of the opening, and can be a B to reinstall if you can't set it up the way it was. Also the metal edge under it is a little sharp.

Now, you're in AZ, so your laws are probably different, but do you get any flack for covering your tail lights like that? I don't know if it'd be a problem here in PA. You can see the brake lights, but what about regular tail lights? Plenty visible?

Hey, Ron just another thing to check, but one of the clamps on my tail pipes was lose and it was causing a rattle. I change it out and that resolved most of my issues.