how can I fix my wd420 washer dryer hotpoint aquarius?

When I try to do a wash (either full or half load) the drum only moves from side to side but when I put it on to spin, it does a full spin and if I run it on an empty wash it does the cycle properly. I have already put two "brains" in it and recently had a thermostat put in for the tumble dryer so is it salvageable or time to cut my losses. It is over five years old