This has been going on for as long as I can remember, but I am feeling what I believe are drivetrain vibrations in my seat when I go WOT in 3rd, 4th, and 5th at around 2750-3200RPMs. A mechanic I know thought it could be one of my front CV-Joints, but I've never felt a CV-Joint do this before. This was also his estimate from just my explaination, never test drove it though.
Was curious on your throughts, seems to happen at full torque.
2010 WRX 5-Door
~75,000 miles (changed my diff. fluids and transmission fluids at ~70,000 miles)
Stage 1 Cobb Tune
DBA 4000 W/ Hawk Brakes (Just installed ~600 Miles ago)
Let me know if you need anymore information, thanks!