ZPmadA

I saw a thread where somebody was trying to diagnose a vibration experience under acceleration and it turned out to be torque tube bearings. I did the torque tube bearing test on my car (rev with clutch pedal down vs. rev with trans in neutral) and both ways had no vibration in the stick. I don't think it is the torque tube. The stick seems to only shake when I'm hitting full boost at higher speeds (mostly 3rd gear) where there would be a higher load. Is this normal, or could my balance shafts require adjusting? Is there something else I could check?

supes6

I am having the same type of issue. There was a vibration at 2500rpm that would go away when I pressed the clutch in. I just had a shop look at it and they found 2 bolts missing that hold the transmission to the torque tube. So fixing that got rid of the vibration at 2500, but now I can feel a different vibration between 3-4k rpm. They put a stethoscope to the torque tube and said it was fine, so I'm at a loss. The axles look fine but I might try re-packing them just in case.

KuHL 951

You can always check the trans mount. Maybe under higher boost it's flexing more and you get that in the shift tube as it contacts the case. It's amazing how far the TA can twist if the mount is bad or worn. Get under the car and try to twist the TA with your hands. They all move a bit but it shouldn't be easy to do by hand. You might be surprised.

V2Rocket

i just rebuilt my TT and put a turbo tranny on my car (dual mounts, not single like you guys have) and my shifter wobbles a little bit when accelerating too so i dont think its really an issue of torque on the trans (my 137ftlbs vs ur 243), maybe just vibration..

i also just replaced the shifter cup bushing and put a new shifter pin on my lever and modified the shift rod to fit within .01" so theres no play there.

TheRealLefty

Oddly, sometimes failing clutch centers can decide to vibrate harmonically at certain RPM's, more common in rubber center OE NA clutches, but also possible on spring clutches, I think.

ZPmadA

Would that only happen when the car is in gear and accelerating? That is the only time I have it shake. Also, it has sat for a while. I wonder flat spots would cause the shifter to shake. That wouldn't explain why it is smooth coasting in neutral or in gear without throttle.

adrial

How many miles on the clutch?

EDIT:
Just realized this is an ancient thread. Slipping clutch could guess the symptoms given in the OP.