I installed a tranny with 150K miles on my 944 a month ago. (i bought the car trannyless). Anyways, i noticed that the car makes a weird sound as if either the driveshaft and/or the transmission is making a sound when it is spinning. When i depress the clutch, the sound goes away. Any ideas what this could be? Has anyone else experienced something like this?

 

Can you describe the sound? What happened to the previous transmission? Could be a clue. I would start, if you haven't already, change the gear lube, be sure to put in the good stuff. It really makes a difference.

 

This sounds like the exact issue that I have. I drive an 86na with only 55K miles and if its in neutral I can hear a slight rattling in the gearbox that disappears when I depress the clutch. I filled up the gearbox with lube last week which was about a quart low. This rid me of the shuttering I had when I slowed down to an idle in 2nd gear, but I still have the slight shutter in first when slowing to idle and the rattle in neutral. If anyone has any insight PLEASE let me know.

 

Most 944 trannies are pretty noisy. I wouldn't worry.

 

that sound goes away when you depress the clutch because it stops the driveshaft from spinnig in the tranny. I wouldnt worry about it. Mine does it too and my tranny has 113k miles on it. As Tabor said, 944's are known to have noisey transmitions.

 

I have the same sound and have tried the same fix as the rest of you, sound is still there. Like the rest of you, the Porsche mechanic said the 944 tranny is usually noisy but very robust.

 

Does the noise only occur while in gear, in neutral or both? Also, this topic was brought up not too long ago under "My tranny makes funny noises!"( http://forums.rennlist.com/scripts/r...&f=15&t=001682 ) I mentioned I had a similar noise problem which was just a loose U-clamp for my exhaust near the center of the car. I would really check these clamps for tightness.