Here's the situation. About 1000mi ago I had the clutch replaced with another stock unit. I have a 2006 Evo IX MR that I run in STU. After about 500mi and during an autocross (Nationals) it developed a loud clunk under braking. This continued and was easily replicated with heavy braking application. I get a few loud clunks that you can feel in the front, followed by a few un-clunks (?) after heavy acceleration. After this it didn't seem to repeat itself until heavy braking again. It is a bit unnerving and seemed to get worse.

My first thought was that something from the clutch install had come loose (motor mounts?), so I took it back to the shop that did the clutch. They confirmed that nothing had come loose and suspected that the AST 5200's upper strut mounts/camber plates were causing the noise.

Based on this I replaced the AST's with the stock Bilsteins and unfortunately that didn't help.

At this point I had no idea what was wrong as I had also checked the obvious stuff (bushings, mounts). I decided to take it to a local dealer. The dealer took a look at the car and apparently put stethoscopes under the hood and identified that they believed something in the drivetrain is causing the noise. They continued the investigation and verified that nothing related to the clutch install was at fault.

Now here comes the odd part. They believe that it is something internal to the transmission. The service manager said that they ran the car after checking the clutch and they can hear something binding in the transmission that doesn't sound healthy. This seems very strange to me because at no point has there been any grinding during shifting or any difficulty during shifting.

I'm going to try to talk to the technician tomorrow to get a better understanding of why he's thinking it's the transmission, but has anyone heard about something like this? Does it sound more like the transfer case / front diff?

I talked to Shepard as they are local to me and they aren't familiar with this type of scenario either. Any thoughts?

 

Thats weird. I see you from ohio, why not check with buschur racing instead of dealer?

 

Buschur actually did the clutch install but it's not easy to get the car out there as I don't have a trailer and it's pretty far from me to arrange a ride. I also thought it would be something more straight-forward or I would have considered somewhere other than a dealer.

 

Good luck!! Does seem strange, I have shared a few thoughts, few more I'll message you with in the a.m.