It seems to be spinning OK. So what is probable problem, how to disassemble and replace? I also hear a clicking sound from the bottomish that seems to correspond to the agitation rate - one click per back and forth of the agitator.

If you have a two stage agitator that the top and bottom are jointed together, you may have defective clutch dogs in the agitator. These are four neoprene (or some other substance) that mesh with a gear in the bottom of the agitator. They wear out (especially when you overload the machine) and will stop the agitator from functioning properly. Grab hold of the top of the agitator and try to spin it by hand in both directions. One direction it should spin freely and in the other it should grab. If it spins freely in both directions you can disassemble it and replace those dogs and you've fixed it.

JimGu, Thank you! May I ask where to start the disassembly process?

I would need to know the model number for exact instructions, but start at the top of the agitator. Remove the fabric softener dispenser, if any, then the cap at the top of the agitator. Most will then have a seal inside that has what looks like a handle to remove it. Just pull up on that and be careful not to break or lose the O ring that is on it. Then you will see a nut down inside there to remove. I believe it is 9/16". Take that out and pull up on the bottom of the agitator. Sometimes takes some effort there. Sit the agitator on the floor and pull off the top part and you will find those four little clutch dogs in there. When you are reassembling it, you'll probably have to hold it sideways to prevent them dropping out, however, some models actually will have a ring that fits down over them to retain them. Remember these are general instructions and you may find variances in different models.

Worked a champ! Thanks again JimGu. Used a touch of vasoline to hold dogs in place, but then had to run very hot water to loosen them. When the wife is happy, I am hopeful of continued life and you will be my secret while I take the glory for being that really capable dude...

Glad to help keep your wife happy. If Momma ain't happy... ain't nobody happy.