2005 SMG - Tinny Rattle from the Back Half of the Car

[Andratch]

Hey Folks,

I recently purchased a 2005 Comp Coupe. I'm going through my new-owner-maintenance steps, and have a quite audible tinny rattle from the rear that is driving my OCD nuts.

• Sound seems to be coming from the rear (tested via speed bump).
• Noise is loudest from the exterior.
• It doesn't appear to be the exhaust.
• It makes the noise in and out of gear.
• It makes the noise with the handbrake on and off.
• It does it in straight lines and turns (thinking its not the diff).
• It isn't rhythmic, I hear it over bumps big and small.
• It has a "dragging an aluminum bat over concrete" kind of sound.

I don't see anything that is obviously loose, beating on things with a rubber mallet doesn't reveal anything, and when I push on each corner of the car i can sometimes get one 'creak' once but nothing more.

Below is a video, you can hear it almost immediately and at random intervals as I drive down my local "bumpy noise test road."

Reading other forums sends me on a wild goose chase of control arm bushings and whatnot....any specific ideas on what to check?

https://youtu.be/eAu9zpnNDxU

[zivagolee]

loose brake pads?

[Andratch]

loose brake pads?

I don't think so. Rattle continues under light braking as well.

[oceansize]

Subframe bushing heatshield?

[Will]

A rock caught between heat shields?

[sapote]

A rock caught between heat shields?

This would cause a continuous scraping noise.
Yes, the noise seems to be from the aluminum heat shield flexing.

[Andratch]

Subframe bushing heatshield?

I'll have to get back underneath and tug on the heat shields. Dang heat shields, can't live with 'em, can't remove all of 'em.

Just another note, I drove the car this afternoon - the noise can't be heard at all from the interior with windows up. But is quite noticeable from the outside. Leads me to think it's not something "big" that would transfer noise through the body.

[Jimbo's M]

A rock caught between heat shields?

My old Prelude had this. Had to remove the shield. Ended up in Urgent Care.

[MacCube]

I have a couple of suggestions that could possibly cause a sound similar to that. The metal underbody cover for the fuel filter being loose and something taping on the side of a rear shock. Just a wild guess.

[Andratch]

Folks, I think I found the source, but I'm confused WHY it's the source.

I put the car on ramps and did some 'push/pull' on the rear sway bar to rock the car, and heard my creaks coming from the REAR LOWER CONTROL ARMS. Both of them. I did the push/pull with my hand on the control arm, i could 'feel' the creak when it happened. I also tapped it with a socket and the tone it produced matches that of the creak.

There's nothing obviously wrong with them - the inner bushings look brand new (I think it had Turner ones on before I bought it, and the previous owner switched back to OEM for the sale). Any idea why this would create a creak?

I don't mind re-buying aftermarket ones, or just some new Lemforder units to swap in - but this one's a bit of a puzzler.

[heinzboehmer]

All bolts tight? I recently had the LCA to subframe bolts come loose on my car. To torque them back up you'll need to modify a socket: https://nam3forum.com/forums/forum/m...847#post210847

[Andratch]

All bolts tight? I recently had the LCA to subframe bolts come loose on my car. To torque them back up you'll need to modify a socket: https://nam3forum.com/forums/forum/m...847#post210847

It sure seems that way. The inner bolt is just a regular old 18mm, I actually loosened it the other day and retightened it because I was afraid it was OVER tight. Outer bolts are also tight.

maybe the inner bushings aren’t seated right? Causing a creak when they move?

[Andratch]

I went ahead and ordered Turner lower rear control arms, hopefully replacing that whole part will eliminate whatever is causing that creaking/popping. Has anyone seen this kind of noise from the control arms before? I'm puzzled as to why they're making that noise.

[sapote]

Folks, I think I found the source, but I'm confused WHY it's the source.

I put the car on ramps and did some 'push/pull' on the rear sway bar to rock the car, and heard my creaks coming from the REAR LOWER CONTROL ARMS. Both of them. I did the push/pull with my hand on the control arm, i could 'feel' the creak when it happened. I also tapped it with a socket and the tone it produced matches that of the creak.

I don't think the LCA metal bar can make this noise by itself -- it's total insulated from the two rubber bushings. Something else must have hit it, or something hit something and not the LCA.

[Sharocks]

OP, get an exhaust.

You will not notice this anymore and you will enjoy the car instead.

You're welcome!