Product review (5 stars): it's an easy swap. Watch some videos on youtube
Your agitator just wiggles back and forth or doesn't do anything? This is most likely the fix. I've done 3 of these now, in rental houses no less, takes about a half hour and a ratchet with an extension. The older stuff can be a bit fiddly to get apart, but once you do, it's an easy swap. Watch some videos on youtube.