Transmission Rattle
 

Hello all,

I was getting ready to get some miles on my new build today and upon start up there was a knocking/rattling sound. I called a buddy over who listened as well at first we thought it was rod knock, however upon closer listening and testing found its coming from the transmission.

It will make the knocking sound while the clutch is released, however while the clutch is pressed in the sound goes away. We tested briefly to see if it would do it with the car in gear but seemed as though it did not do it. He doesn't know evo's all that well so mentioned starting a thread and then also seeing if someone in the PDX/Vancouver area is available just to lend a 2nd set of ears/eyes to either confirm or assist in troubleshooting the issue so that the car can get on the road.

Thank you

James

This seems to be happening a lot lately. Ive been unlucky enough to experience this twice. I knew it well enough the 2nd time just hearing it knowing what was wrong from my first experience. HOPEFULLY for your sake Im wrong, but from my experience, the flywheel bolts backed out and the flywheel was slapping against the crank. At idle it sounds like a loud WHONK WHONK WHONK noise, and while driving its like a very dense, ringy metallic buzz.

Clutch in, it does go away because the throwout bearing is forcing the whole unit to actually press against the crank. Without being pressed, it would rattle because theres no pressure on it.

Has your clutch engagement become different?

The engagement hasnt really changed, but then again I wouldnt know too much as its only been driven 5 miles since being put together. it doesnt make the loud knocking and then goes away with pdeal pressed.

What kind of clutch do you have, ever since my QM 8 leg went in I have similar maybe same sound from time to time, but when I push my clutch in and release it again it usually doesn't come back.

Act solid hub street disc.

My Exedy triple makes all sorts of awesome noises. I sometimes hear a similar noise but when I press the clutch pedal it goes away (and the standard triple plate noise starts). I then let out the clutch pedal and that sound isn't normally there for a while.

The sound is a metal on metal not griding but contact sound. I should have answers on what it is either tonite or tomorow depending on how motivated I am to get the transmission off the car

Let us know, sounds like YAHU and me have the same sound.

5th gear rattle that is common in the 03 VIII. Mitsu changed the output shaft in 04+ and discontinued the 03 and down.

Aaron this sounded like rod knock, it was louder than the engine/exhaust at a 3500 RPM rev(how we determined it wasn't from engine).

I should have the transmission off tomorrow however my arch nemesis will rear its ugly head.. and its that stupid damn'd locking clip on the input shaft. Anyone have any really good advice.... I couldn't for the life of me get that damn thing off last time.

Get a push type clutch and a hydraulic release bearing.

Thats exactly how the 5th gear rattle sounds. It might be something else entirely but the description and year match a known problem is all I mean.

I'll still pull the trans just for peice of mind. If it still does it on start up take a video and post it.

Is the 5th gear rattle something that will need to be addressed in a rebuild or just something that is there and is not a transmission threatening item?

And back together and all that jazz.

Still does the rattle however it only does it below 1000RPMS, and once the car has had about 3 minutes to actualy idle and warm up the idle is sitting right at around 1000RPM so you can randomly hear it happen but not consistant.

Ya, I just call that normal.