I installed this on a 2001 S4. This had the same dimensions and fit well. There were two very minor points that kept me from giving it a 5. There was a vent hole in the Al casting that wasn't completely cleaned out. The stock starter has a plastic isolator on the solenoid larger terminal. This could be moved over to the new unit, but an extra nut or spacer is required to use it. Overall I would recommend this unit.