Recall reading something in Consumer Reports (1980's? 1970's?, not sure) lifetime or very long warranties on things like tubs, motors and transmissions weren't a huge benefit. Usually anything that didn't break within first year of use would last a very long time.
This and besides by the time a major part such as tub, transmission or motor *did* finally give out, the appliance in question likely would need other repairs as to make replacement not worth bothering.
Case in point when my Frigidaire (from 1950's) ironer gave out (stripped gears), the motor was perfectly fine. Perhaps if replacement parts were still available tearing the thing down and fixing would have been an option. But one wonders even in 1950's or 1960's if average housewife would have bothered given likely cost.
Have seen pictures of vintage washing machines with enameled tubs that look almost new. Rest of the thing is clapped out, but there you are.