WM31 Help! Changed suspension but the knocking is still there??

I have changed both suspension rods but now I have a sneaky feeling that it may be the bearings that are making the noise. I sounds pretty noisy anyway when it spins but every now and then when the contents are out of balance it makes the most horrendous noise and I race out to switch it off! Yes that bad, like the wee guy inside has had enough and wants out! I'm fed up and would appreciate any advice. The whole bearing/spider kit is about £50...is it good money after bad? But it is a good machine, albeit 11 years old now. If you have any ideas, please let me know. Thanks!