Using this KEIN rear differential mount is easy. First, locate the existing factory holes on the inside of the rear sub - frame of your 2002 - 2007 Subaru WRX or 2004 - 2007 Subaru STI. Then, simply bolt the mount onto these holes. You'll start enjoying better acceleration and control right away. Here are some things to keep in mind. You might notice a bit more drivetrain noise in the cabin because the rubber OEM diff carriers are replaced. As for maintenance, regularly check the bolts to make sure they are tight. Wipe down the mount occasionally to keep it clean. The durable powder coating protects it well, but if you see any signs of wear, you can have it recoated. With proper use and care, this mount will serve you well for a long time, thanks to its 2 - year warranty.