The only thing I know about washers is there are these plastic "dog ears" under the agitator, that if broken, the agitator won't hardly do anything. They keep the agitator turning in one direction only. If you can turn it either way by hand, they're broken.
It is a common thing, they are cheap. If you have to take the agitator off, might as well replace them.
97 T-Bird LX 4.6 - 68k miles
94 Supra TT Auto - street/strip car
04 Crown Vic Police Interceptor - Brenda's car
95 T-Bird LX 4.6 - fully optioned, owned 15 years
96 Cougar XR-7 4.6- Brenda's car, owned 11 years
88 T-Bird 3.8 - first T-Bird, owned 5 years