Sometimes we cannot think of what is wrong. In your situation the opposite is true, there are too many candidates for me to render an opinion. Your problem is one that we really need to be in front of to see and listen to.

Some guidelines can be your springs (you cannot tell about them by looking), the brake, the transmission, snubber or other parts of the support. You also need to check to see if something is caught between the tub and basket.

Here is the service manual for your model.

http://www.servicematters.com/m...ibrary/docs/16023083.pdf

Here is a tech bulletin on a similar problem. It will describe in detail the process of replacing the base including special tools that you will need.

http://www.servicematters.com/m...ary/docs/TDL-0050B-B.pdf[URL="http://www.servicematters.com/maytag_library/docs/TDL-0084-B.pdf"][/URL]

I think your first step would be to take off the front and observe it and the problem and see if that gives you some insight.