Vibration mounts (1) for automotive engines comprise spaced metal mounting brackets (2,4) are bonded to a MDI polyurethane cushioning medium (6) cast therebetween. The brackets (2,4) are marine grade stainless steel and are grit blasted before coating with a primer surfacing before the cushioning medium (6) is cast therebetween. After removal from a casting mould, the cushioning medium (6) in the brackets is subject to postcuring at 75.degree.-150.degree. C. for from 12-24 hours and thereafter is conditioned by storage at 15.degree.-35.degree. C. for a period of from 15-45 days to maximize the strength of the cushioning material.