This past weekend I put in the third Duralast remanufactured alternator into my 2007 4.7L V8 in less than 6 years. This last one was only 2 years old and the one before that was about the same age (2-3 years old). With my driving this equates to 20-30k miles before each failed. Are the Duralast reman's just that bad? Or could there be something else wrong? I don't have any strange "leaks" where the battery is drained slowly, it can sit for 2+ weeks and fire right up. Thanks for everyone's help, perhaps I should just spend the $$ on a rebuilt Denso unit.

PS - if anyone hasn't done the alternator on the V8 it isn't super fun... However, if you take off the pulley from the power steering pump, then take the pump off and move it to the side, the alternator can come out through the wheel well. The tire can stay on if you turn the wheel. I also took off the air intake and coolant reservoir, but those might not be necessary to remove.