Out bedding my new pads today and had to turn around on a hill to avoid a creek crossing. While reversing, I had to let the clutch out rather hard to avoid rolling forward too much, and when I did that, I hear and felt a loud clang from the center of the car. Easing it home, I found that I could recreate the noise with moderate to hard clutch engagements, like a light launch or harder shift, harder loads if you will. Got home and put the car in the air, the noise is definitely coming from the driveshaft, but the cause I am unsure of. There is a slight amount of play at the front u-joint. The only changes I have made to the car recently have been swapping my Tokico Illuminas for V-Maxx coilovers. Car drives fine in gear and the anomaly does not happen when shifting normally and and easing into 1st.

Clutch is an ACT 6 puck going through a 99 6-speed.

Bad u-joints are all I can really come up with, anyone else had this issue?

 

Did your ride height change - even just a tiny bit - when you replaced your suspension?
Your exhaust may be hitting/touching/contacting your rear axle in the right conditions. That happened to me.

Also, is your PPF height set correctly?

And, do check your Rear Upper Control Arm bushings and see if they have slipped in their sleeves.
You will get funny noises if they slip and rest on one mounting tab rather than sitting in between those tabs.

 

The ride height did most likely change after replacing the coilovers. I have an aftermarket exhaust and it doesn't have any marks of coming in contact with something.

I removed the driveshaft to inspect it and it doesn't seem to have any play, but i was going to throw a new one in tonight to see if that changes anything. I'm looking around at other spots in the car. I don't know if i have tunnel vision or not but I'm trying to figure out what could be either hitting the driveshaft or making the driveshaft make that noise. I tapped it with a hammer when i got home and it's definitely the driveshaft.

I also was not aware of the PPF height being something that is set.

 

Here is the sound

 

Replaced driveshaft and that appears to have fixed it