My top load washer is making a loud rattling sound when agitating and/or spinning. It fills and drains just fine. It washes and spins okay, but spun clothes are slightly more damp than before. There is no noise when draining--just the happy hum of the motor and pump (new pump last year)--until the drum gets to about half speed.

I took the cabinet apart and inspected what little I know about. I pulled up on the inner tub and there's just a little play but nothing I would call excessive (not that I would know any better). I tugged and pushed on all the mechanical connections under the drum to feel for looseness or broken parts, but everything appears to be intact and solid. I manually rotated the drum and agitator--thinking it might be a bearing--but both rotate free and smooth without any noise. I took the agitator off and visually inspected the drive block and spanner nut. Everything looks tight and normal. I wanted to disassemble it further, but I don't have the spanner wrench for the tub nut.

I think I'm on to checking the transmission, but have no idea where or how to start. Is there a way to diagnose this problem that y'all could walk me through?

Thanks for the tips. Since my first post I've pulled the motor and gearcase. Both appear to be fine. The gearcase had a couple drops of oil from the vent on top but the rest of it is sound. I operated the drive in both directions and the shaft/clutch turn the ways their supposed to. There's no grit or noise.

With the gearcase off I inspected the brake and clutch. Everything is in good condition and working properly. The isolator in the motor coupling is a bit worn, but nothing is cracked or failing. I cleaned and reassembled everything to test: the tub filled and the agitator still made the grinding/rattling noise. This time, however, it wouldn't spin or drain.

So I took it all apart again to find that in pulling the motor I must've broken one of the electrical terminals, so now I've got to replace that part before I can do any further testing. But I've pulled each of the primary assemblies save the drum, and all seem to be fine. I'm well and truly stumped.

And just to highlight the day, I managed to break a small leak into the hot water stop valve (at a badly corroded FIP joint) when I was disconnecting the supply hose. Seems about right for how my projects usually go. :(

Well, for posterity's sake I'll update:

I found a used machine with compatible parts nearby for cheap, so I brought it home and started swapping stuff out. Turns out it was the motor on the old machine. It was making that terrible "clackety-clackety" noise during agitation and spin. It got really bad really fast in the "new" machine.

So I took my newer parts (pump, motor coupling, misc clips) off the old machine and put them in the "new" machine. Voila. Back to doing laundry.

Huzzah.