Manual Transmission - Need help diagnosing metallic noise... transmission??

I posted a similiar thread last month in the engine section, but now I think this noise is tranny related. As for the trans, it has a LS7 clutch, new slave, and new throwout bearing. Installed 4K miles ago. The squeaking is either coming through the exhaust or from the bellhousing. I used an automotive stethescope on it. Some sound from the bellhousing, but nothing definitive.

Video is included below:

Here's the rundown:
1. Noise is loudest at start-up. Seems to quiet a bit once the engine is warm.
2. Squeaking frequency increases as RPM increases, till about 3K RPM.
3. Squeak is most prominent on the passenger side of the car.
4. Pulled the trans. Noise went away when running car w/out it (but with the flywheel installed).
5. 8. WHEN LETTING OUT THE CLUTCH IN REVERSE, THE NOISE GOES AWAY...UNTIL THE CLUTCH IS FULLY ENGAGED.
6. TRANS FLUID WAS SMELLING LIKE IT WAS OVERHEATING ON LONG INTERSTATE TRIPS WHEN IN 6th GEAR (OVER 30 MILES) I had replaced the oil with Dextron IV conventional after the clutch swap.
7. Noise started abruptly when I was driving to work last month. Had to drive the car about 75 miles to ship from Germany back to the USA. Car drove fine, even at 90mph on the German Autobahn. Power felt normal. The AFR was 14.6 at cruise and 12.4 WOT, so it seems normal.

http://youtu.be/6GPkm7OFlj0

[URL="http://www.youtube.com/watch?v=C6RXNv-3-rI"[/URL]

Throwout bearing has some fore/aft slop in it (about 1/8"). Doesn't seem normal to me. Think that was the problem??

$0.02 appreciated.

It sounds like it could be Lifter and/or pushrod issue. What lifters are in the car? Any exhaust leaks showing up on the exhaust anywhere? Doe it do it while your car is in forward motion?

It sounds like it could be Lifter and/or pushrod issue. What lifters are in the car? Any exhaust leaks showing up on the exhaust anywhere? Doe it do it while your car is in forward motion?

Thanks for the response. Yes, it makes the same sound in forward motion. The car has LS7 lifters. About 25K miles on them since my last head/cam change. I didn't pull any pushrods to check for straightness, just the rockers to make sure the trunion bearings didn't come apart.

Guess a lifter makes sense as the sound isn't as loud once the car warms up. The spark plugs on the passenger side all looked the same (light grey on the tips), so that's not helping me isolate a lifter if that is the issue......

Being in Germany, they are a$$hats about exhaust leaks. All the couplings are sealed with exhaust paste. I only have about 3K miles on the exhaust, to include the converters. That said, would an exhaust leak make that kind of sound?

Thanks again.

I have heard some pretty nasty exhaust leaks with ticking sounds. Could be I would rule out the simple stuff first before digging into the more complicated stuff. Exhaust leak the sound wouldnt get softer as the car warmed up though... :bang:

I have heard some pretty nasty exhaust leaks with ticking sounds. Could be I would rule out the simple stuff first before digging into the more complicated stuff. Exhaust leak the sound wouldnt get softer as the car warmed up though... :bang:

Thanks for the second post. Guess if it is an exhaust leak, then it shouldn't hurt anything.... and it certainly would be a rattling, nasty exhaust leak.

I'm shipping the car from Germany to the US on Monday. I'll be able to troubleshoot more in-depth once it arrives. I'm afraid to tear into it too much now, as the car has to drive under it's own power for shipping.

Thanks again. Had 78 people check my related thread in the Internal Engine section... but nobody has yet to offer advice or wild speculation. :)

Well, I'm pretty suprised that across the nation nobody knows what was making this noise in my original post. I still don't have it 100% figured out.... but it's definitely tranny related. I pulled the trans and ran the car w/out it (but with the flywheel installed). Noise gone.

Had a fair amount of slop in the throwout bearing. Not sure that's it, but replacing anyhow. Guess if it squeals when I reinstall today... then the trans itself is F'd. Will post results once done.

Update: problem found. It was the trans itself. Va Speed installed a new level4 T56 and all is quiet now. Theyre supposed to contact me after the trans company tears down my old tranny. .. to tell me exactly which bearing went bad. I spent a lot of time in Germany ballin on the Autobahn in 6th gear, so Im guessing I fried that bearing.
Anyhow, seen a couple related postz over the past 2 years with no answer. Hope this helps peeps in the future :)

dude i love your intake manifold, i dont that would ever look as cool on my LT1