IW STi Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
248 Posts
Discussion Starter #1
Hello,

Car:
2006 STi

Mods:
FP Green, COBB TBE, Grimspeed Headers, up pipe, process west too mount, K&N Intake, ID1000s, protuned at GST, etc etc.

Problem:

Recently in the rain I’ve been hearing a loud rotational metal on metal banging sound coming from what seems to be the transmission area directly under the shift linkage area. The noise has only occurred when it’s raining. Over the past year it’s rained maybe 6 times. It happens every time I get up to highway speeds in the rain. Once I exit the highway and stop the vehicle the noise goes away and unless I reach highway speeds again, the noise does not come back.

Again, it has never happened on dry roads/dry days.

Currently the flange With a single bolt on the downpipe that connects the downpipe to the frame of the car is broken so the downpipe has more play. I’m not sure if the downpipe is hitting the transmission or the driveshaft once the exhaust hangers get wet and loosen up?? I’m going to take the car to an exhaust shop Wednesday and have that welded back together.

My only other idea is the center diff. Changing the DCCD settings does not effecr the noise. The DCCD does go into LOCK, and there doesn’t seem to be any issues around the DCCD that I can tell. However I am not very knowledgeable in regards to the subaru DCCDs.

Below is a video of the noise. I apologize for the poor video angle and quality but I think the noise is very clear. You can see in the video the noise does stop and start again based on speed.


Any help is appreciated!!

Thank you everyone.
 

·
Premium Member
Joined
·
5,202 Posts
Water is hitting something?
Have to ask, you have a stock undertray?
Also inspect V shaped areas starting at the back of your front wheel wells.
Is your DP/exhaust low?
 

·
Registered
Joined
·
248 Posts
Discussion Starter #3
I have an aftermarket up pipe, which I’ve heard can lower where the turbo sits and cause rattling/running from the exhaust hitting the driveshaft.

my downpipe might be the culprit. The flange at the bottom of the downpipe with 1 bolt that connects the downpipe to the trans/frame is broke /snapped so the downpipe has a lot of free play. I’m thinking when the rain gets everything wet underneath and lubes the exhaust hangers there’s extra movement that causes the rubbing??
I’ve only had this happen when it’s wet. Which is so weird to me.
I just hope it’s not my center diff/trans.
 

·
Premium Member
Joined
·
5,202 Posts
I have an aftermarket up pipe, which I’ve heard can lower where the turbo sits and cause rattling/running from the exhaust hitting the driveshaft.

my downpipe might be the culprit. The flange at the bottom of the downpipe with 1 bolt that connects the downpipe to the trans/frame is broke /snapped so the downpipe has a lot of free play.
There will be marks from this. Just look!!!

I’m thinking when the rain gets everything wet underneath and lubes the exhaust hangers there’s extra movement that causes the rubbing??
I’ve only had this happen when it’s wet. Which is so weird to me.
I just hope it’s not my center diff/trans.
I seriously doubt wet hangers are the issue.
Not (inside) your center diff. It doesn't get wet.

Water is hitting something - exactly what is making the noise can be hard to discern. More so on line. That said, your down pipe is in the V behind the front passenger wheel.
 

·
Registered
Joined
·
248 Posts
Discussion Starter #6
Update :
I believe I found the issue if anyone is interested.

Got under the car and couldn’t see any contact with the frame. I did find a spot where the driveshaft was banging the midpipe, directly under the drivers and passengers seat, which is exactly where I felt and heard the noise.

https://i.imgur.com/O7uZaKH.jpg

https://i.imgur.com/BWNLFul.jpg

It is right where the carrier bearing sits, and the carrier bearing did have some play, but not much play downward. Only when I pushed upward. Still might need to be replaced, and unfortunately that required the entire driveshaft to be replaced.

https://i.imgur.com/SJJUiai.jpg

The bracket on the downpipe was snapped off, so I had a welder fix it and position the exhaust with more clearance, hopefully this solves the problem!

https://i.imgur.com/qPC5mzv.jpg

Still Completely lost as to why I was only getting contact and noise in the rain????

Hopefully my issue is solved!



 

·
Premium Member
Joined
·
5,202 Posts
:)

DS: Time for a CFDS? Preferably from the DSS.

I never intended to mod - and this is the part that got me hooked . . . dealer informed me I needed a DS due to worn carrier bearing. I went looking to do it cheaper. I didn't get cheaper. But I got rid of the carrier bearing :) Course I then realized all I had was strut clunk, not carrier bearing noise . . .

Added: so I got to go looking for struts . . .
 

·
Registered
Joined
·
248 Posts
Discussion Starter #8
LOL, well if I replace the DS I’ll likely just go CF. OEM DS is ~$750 so why not go for the carbon at that point???
 
1 - 8 of 8 Posts
Top