One thing you might try is placing a video cam under the car with the car on jackstands or even better a dyno and see if you can tell from the video what might be going on. I did this when I hunted down my vibe issue and it help a little...its an idea.

 

Gun

I threw the car up on jack stands and started it. I put it in 2nd and let it idle while i reached under it and videoed the drive shaft. There is a clear bounce and imbalance on the shaft. here is the link: http://www.youtube.com/watch?v=9Ji9x...yUaoRnH58n6nQ=



THis pisses me off because i have had it to shoip two different times to have it balanced. It is clearly off.

 

Did you place the jackstands so they held the car up from the rear axel? That way the suspension is still loaded like it would be on the road.

When the vibration is bad can you really feel it in the shifter handle?

-Gun

 

yes and yes!
the vibe is all through the car! check the video. Im gonna take it down to the shaft shop on monday!

 

if you watch it at about 40 sec. it really shows.

 

here is what mine looked like..
http://www.3rflying.com/slipyokedyno.mp4

The vibration is very high frequency and you cant really see any thing runout. However if you watch the oil drop coming from the TS seal you'll see it spread out as the vibration starts up. The car was hooked up to a dyno during this...this type of dyno bolts to the axel hub after removing both rear wheels.

This vibration occurred around 2400 RPM in 5th gear.

 

well my quest is over. I found the dam problem and it is solved. I took my car to the shop that built my shaft and showed them the video. Even though they were completely busy they went ahead and built me an entirely new driveshaft. However, they did it out of aluminum. I did voluntarily pay the difference between the steel shaft that i had already paid for and the cost of a new one.

I took that bitch down the freeway at 100mph and popped it out of gear and it is as smooth and quiet as my scion. I love it.

However, I now realize how much noise and vibration is coming from my exhaust. It is rubber mounted under the rear seats but also dumps out there as well. So this weekend I am going to get some new rubber mounts and remount it. Im also going to use the fatmat that i have left and do the inside of the trunk.

I am so friggin happy. 6 months dealing with this crap!

 

Awesome..trying to reuse my old DS was the largest mistake I made during my T5 swap...I ended up like you chasing problems when I should have just got a new DS.

Denny's Damnit!

 

sweeeeeeet :-)
looking at your video it looks to me your old shaft was a bit short ????!!!!

 

+1 on this.
It looks like the driveshaft spline might not have enough engagement to the transmission output shaft. This can make a nasty and unsafe vibration.