Dan, the Signature 18 set was purchased in late 1967. As stated above, my dad replaced the transmission a little over a year later. That repair lasted less than six years before the tranny started to sound like an Airbus A300 up close and personal on take-off, and it just grew louder and louder. I even ran a load of laundry with the intention of shaming my parents when they had a group of guests over, and that at least generated a few comments about the racket.
I know you've seen the picture of the scored piece of tile that was located dead center underneath that dreadful Snorge, and that's not the only incidence I've heard about, although the other one was on a carpeted surface (who has carpet in their laundry area?).
It wasn't until mid-1975 that I took my mom to Sears while my dad was out of town on business and we found relief in a new Kenmore with Quiet Pak transmission, one notch lower than a Lady K. That machine served in relative silence for over 25 years at which point it started to produce a sewer smell when it drained, and my mom decided to call her home warranty company to have it repaired. They chose to replace it and gave her a crap BOL GE. This happened while I was out of the country, otherwise I would have put a stop to the process. I'm sure a new drain hose, pump or filter or maybe all three would have solved the problem, and those would have been simple repairs I could have made. The only repairs I did make over that 25 year period were replacement of the belt once (the original skinny green Quiet Pak ones were notorious for failure), and replacement of a leaky flexing filter with one of a vastly improved design, also only once.
