I've been trying to track down a vibration that I get when I get close to 3k and the tc is locked....this vibration only occurs sometimes.

At times, can hold it in third gear, past 3k, and the car feels smooth and comfortable. But most, as my rpm's rise from 2.5k, the car starts to vibrate more and more, to the point where I have to throw it into OD to get rid of the vibration.

My trans and tc were both looked at half a year ago. But I don't think that's the culprit.

Im thinking it could be my toque arm or driveshaft. Or both. Still running the stock torque arm, and I am pretty lowered. Or could it be that my u-joint need changing?

what do you guys think.

Any advice would be great. thanks.