Chaz58 Sounds like you'll have to take it out and remove the side cover look in there for chipped gears. It's not rocket science but there is a lot of rollers and washers and entrails to fall out,have your service book handy. Now that's not so bad on just the sidecover just gotta hit the drum and low reverse slider to put it back on. Input shaft is full of rollers,hold them in place with grease,not bad to put it in the freezer in hot weather till you can "stab" it. As kids we soon learned the "tricks" !!