My 2003 Scenic seems to go through ball joints fairly quickly. I know the roads around here are not in the best shape, but surely they should last for more than a year, which appears to be around the average length of time they last. The ones on at the moment were bought from Europarts I think. One thing I have just noticed is that in the Haynes manual they mention a "plastic protector plate" and I read somewhere that this goes between the ball/boot and the suspension arm. I cannot remember this ever being fitted on my vehicle, and certainly is not supplied as part of the ball joint "kits" I have purchased. What is the purpose of this disc, and could this be the cause of reduced lifespan for the ball joints ?