In certain cases, we have had to replace the spinner basket due to loss of its water charge in the front cartridge. You may have noticed that when you spin the basket by hand, you can hear water swirling in the front area. This is not water left over from a wash cycle, but a 30 ounce charge of a saline solution that is sealed in the front spinner cover for balance purposes. In fact, Maytag did away with the lower concrete block that was placed under the tub on earlier models since the balance ring proved so effective.
Since the stainless steel spinner basket is the only part on the machine with a lifetime warranty, you should try for a new one if possible. They can get out of balance.