These machines are notorious for eating belts in relatively short order.

The rest of what you're describing seems unusual, as SQ machines have good longevity other than their appetite for belts.

Others here will be able to suggest what may be causing the bigger problems and what, if anything, you may need to replace.  It would be a good idea to police the overloading situation.  That's hard on any make of washer and it's possible there's more than just that one sock that ended up in between the tubs.

Look at the belt when running, pull on the idler when spinning, if it spins normally then replace Idler assembly and belt if worn.

If it still won't get up to speed in spin [ washer should whistle when spinning at high speed with no clothing in basket ] you may still have something stuck between tubs.

These washers are pretty rugged, but they are not simple mechanically or easy to do many repairs on. If you want simple and easy to repair plus best reliability get the SQ Front Load Machine, it is a far better washer, it does 50% more laundry per load while using 1/3 the water and it gets things cleaner and drier.

John L.

Hi, Try pulling on the idler and see if it spins properly, even though they have been replaced that does not guarantee they are adjusted-installed properly.

Save your money on another motor or transmission, those are never the cause of a slow spin, it could be bad top bearings and seal however, or the brakes dragging.

John L.