Originally Posted by TJMac

You might check the gear box housing itself. There's a post in this tread IIRC about a problem with a cracked gearbox causing excessive wear on the gears. I don't remember exactly, but replacing the actual housing solved the problem. Also, I used more diff lube on the gears than what is stated in the manual and to date, I have yet to replace any gears (bought the car in July).

If AE offered steel gears, even at $30-40 per gear box, I'd be all over it.