Snowrydr01

Backstory = I bought the car (2014 IS350 F-sport RWD) used with 30k on it less then a year old and that was a little over 2 years ago and this noise has been driving me mad ever since. I brought it to the dealer and after 2 days they eventually gave up and said they THINK its coming from above the heat shield and it would require removing the entire rear axle to get to it and if it was a twig of something warranty wouldn't cover it and it would be out of pocket. I am pretty sure it was a scare tactic that worked.

Symptoms =
When going over choppy bumps it is a light (thin) metal sound (but loud) almost like a lose heat shield (its not i checked when swapping summer to winters).
The timing seems to be more on suspension droop then on compression.
Sometimes i can get it to make the noise if i jerk the wheel left and right and shift the weight left to right or right to left. Which made me think maybe sway bar end links but i couldnt find any play in them at all.
It is temperature dependent. It is louder and consistent in the summer and minor in the winter but increases as the distance i drive and heat is generated. Which make me think bushing somewhere.
Manageable with windows up and stereo loud, but sounds like a jalopy with the windows down.
I have also checked repeatedly if i had any vertical, 1 to 6, or 9 to 3 play and there isn't anything obvious.
Also cannot replicate the noise by hand pressing down on the corners while parked.

Its not the gas cap door, that is another equally annoying noise from the rear.
It is not the exhaust shifting around

This is my big spring goal and would love any help before i just start buying parts and replacing things blindly.

chyeea03

Is this noise coming from the left or right side? Are you able to tell?

I'm having a rear clunking noise going over bumpy roads as well (though not a metal sound) coming from what sounds like the rear passenger side. Initially I had thought it was the portable jack that came loose but I think I can rule that out.

Snowrydr01

it is primarily the left side but sometimes if i hit a pothole on the right i still hear it. Another reason that i am leaning towards sway bar links or something of the sort.

jkonquer

rL-gT

There's a TSB for that noise.

Snowrydr01

I should've put that in the initial description. I tried this years ago when i noticed it first and it had no effect on the noise.

Snowrydr01

which TSB are you referring to? The closest i could find was for squealing brakes and excessive brake dust and that is not relevant here as my noise is a pronounced clunking.

At first i had thought maybe it was the calipers or pads bouncing around but i can still make the noise happen when going over bumps while on the brakes slightly which would mean that the calipers are now in a fixed position.

rL-gT

There's a TSB for the rear brake shoes not being secured properly which would cause a metal clunking noise from the rear wheel area

It's there. Keep searching.

Snowrydr01

is this the one you are thinking of?

http://www.revbase.com/BBBMotor/TSb/...dPdf?id=192695

rL-gT

Yep. That's the one.

Snowrydr01

Thanks for the direction, it took a while to find a version that wasn't behind a pay wall. Of course it was released 4 months after i brought my car in to be looked at and was scared off by the dealer. I had to replace rear disks and pads in the spring anyway so i will do this while i am in there and report back.

I am a bit pessimistic though since the noise is temperature dependent and a variability like that always makes me think rubber as the first culprit.

LexoDAV

2013FSport

iTrader: (2)

A couple of things come to mind, remove everything from the trunk that comes out easily. Test drive.

With the help of a trusted friend, look under the car at the rear diff and with wheel chocks in place and trusted friend, place in drive and apply some throttle. Now watch and listen to rear diff for movement and noise. Some movement is ok. Repeat in reverse. A drive on lift would be best...
Remove one end link from the anti-sway bar. Be wise with your steering inputs when test driving.

With these items done, that leaves exhaust, maybe the e-brake pads, heat shields etc.
Good luck!

Stock shocks and springs or ???