Ever since I installed the floor mounted Spohn Torque Arm the vehicle has developled a vibration that starts at 3600 RPM and continues through 4000 RPM. Its quite severe in the area of the center console but seems to light up the whole vehicle. I have set the angle of the pinion at various locations from +2 to -3 and it still vibrates. It seems to get better when the angle is set as recommended (0 for street driving) but is still there. I have also rotated the driveshaft 180 degrees to verifiy that it wasn't causing the problem. I even went as far as fabricating some thicker rubber isolators for the floor mount. At this point, I'm at a loss on how to proceed. I could live with the feel, but I'm starting to get worried that I'm going to break something. Any ideas?