So far two Bosch alternators have broke on me. The first one came on the car and the bearing got really loud. Now my next one off a parts car basically stopped working. I hit a high RPM, below the redline, and all of my dash lights went out for a second and it doesn't produce any power. I'll put in another spare Denso one and I bet it will out last the new looking Bosch ones. I heard Bosch was crap...but holy crap!