BlackPine

Hey guys, I got my 2004 V1 about 6 months ago and I’ve had this vibration at 90mph since. I thought it was the engine mounts and tranny mounts since they’re known to go bad but once I noticed it happened at 90mph in any gear I dismissed that theory. Although I know I’m going to have to change the mounts I think this problem might be stemming from the driveshaft even though the previous owner installed a 1 piece aluminum driveshaft. Could it be that it wasn’t balanced properly. Any thoughts?

(I can’t seem to figure out how to upload a video but the whole center consol shakes like a Jack hammer. Here’s a YouTube link to the vid: https://youtube.com/shorts/cv8pBuTgNa4?feature=share)

98CayenneT/A

I would start with a road force balance of all wheels. It's insane the amount of vibration poorly balanced wheels/ tires can have.

Vcaddy71

iTrader: (2)

I had a very similar issue with 1 piece driveshaft. Mine is more based at a specific rpm range(high) and while troubleshooting with clocking and shimming trans mount I was able to change severity I have thus far been unable to completely eliminate. Currently it's sitting in the box in my garage. If I'm not mistaken DSS changed U joint to a dual cv to help with this.

Rt Jam

You could eliminate the wheels/tires from you diagnosis.

Remove the rear wheels. Jack up the car and hold it up by the outermost point on the rear lower control arms. Reinstall the wheel nuts.
Spin the car up to 90mph and report the vibration.