sf 6500 px?

The washer washes and will not always drain and a lot of the time there is a dirty greasy mess on the clothes, please can you tell me why this is happening. My husband cleaned the drain pump, first off it would not work, he then tapped it with screwdriver and it worked, not always though. Could the grease-mark be due to a broken seal on the agitator drive?? Machine is 10yrs old..maybe I need a new one?