shuboyje,
What I meant when I said I stripped the 4th and 5th gears is that I broke the internal gears, and these will be the 4th and 5th gear parts I've had to order. Sorry for the poor wording.
TXCraig1,
While I'm not excited that the mixer has broken at this rate, it is nice to know that I'm not the only one having problems. I thought at first that I must be pushing the mixer to do something it wasn't designed to do, and got Kitchenaid to replace it once.