There is a curious rattle in the trans

[skidd]

I'm hoping some T5 experts can offer some opinions on a strange rattle that seems to be coming from my Trans.

When sitting still and idling, there is a light rattle that seems to be coming from the trans. It's not very loud at all.
I jacked up the car and crawled under while it was idling. Hard to say exactly where, but it seemed to be focused near the middle of the trans.
It's the kind of rattle that sounds like.. well.. almost like a lose bolt has allowed some sort of bracket to just rattle around a bit from the shake of the cam.
I tried taking a video of the rattle, but the rest of the car is just too loud for the mic to puck up the rattle.
- In neutral with the clutch both in our out, the rattle is there.
- In gear with the clutch in, the rattle is there.
- In any gear, with the clutch out and wheels free-spinning (up on jack stands) the rattle is gone.
- No rattle at any time while driving in gear. Accelerating, Decelerating. HighVac steady cruise at any speed. Nothing.
- Doesn't seem to rattle when the car is cold, only once warmed up.

Any theories?

P.S.
Used T5z behind a mild 302 (e303, GT40p, 600cfm carb) with new stock fox mustang clutch & PP.
Solid Engine Mounts, and new stock fox mustang rubber Trans mount.

[skidd]

Correction.. I do hear it under light loads in any gear. I just never noticed it before. You see, my right ear is pretty weak, but my left ear is excellent.
Let my wife drive as we went for a cruise today. With my left hear towards the trans, I could hear the rattle while she was driving.

[RickP]

How much fluid do you have in the T5?

[skidd]

I'll re check it, but just shy of 3 qts.

[cv2065]

Driveshaft bolts? Shaved mine to fit flush.

[edwardb]

Check your clutch fork, pivot ball, throw-out bearing assembly. Make sure all is assembled and hooked up properly. A build buddy just went through something similar. A rattling sound that by all accounts, including multiple videos, sounded like it was coming from the transmission. Took it all back apart and even sent the transmission back for service, with no trouble found. Found the clutch fork unhooked from the pivot, which likely happened during assembly. The noise changed based on whether the clutch was in or out, etc.

[skidd]

The rattle doesn't seem to change when I press or release the clutch. I don't think it could be that. Though, I will still make sure of course.

[PG_Cobra]

If its coming from the T5 it could be a selector fork pad fallen off through wear.