Help!!! Ive got a knocking noise coming from the rear N/S cant seem to pinpoint what is causing it. If you driving along the road youcan hear it knocking as you go over bumps the bump doesnt have to be substantial either a manhole cover will produce the same noise. I thought it be a broken exhaust support arm but they are all ok. Its annoying to say the least. I thought it might be a droplink or antirollbar bush or arm but i cant see anything obvious but its there when you drive slowly or quickly on normal raods. never hear it on the flat motorways help needed please its driving me mad.