I recently got an LS1 aluminum driveshaft and now I am getting a vibration I didn't have before. Its not huge, I can only feel it in my seat when I am coasting at low speeds. I assume it has somthing to to do with the driveshaft as it didn't do this with my stock steel one. The seller said this one had 70k on it. Any help is apreciated, Thanks.

 

seems pretty simple to me. you have a vibration after you changed drive shafts. change it back and the vibration should go away.