Hello, I have a C4 coupe vtr+ 1.6hdi 2007, I took the car in for a fixed price change of the back brakes, on the paper work I have warning about the ns cv boot being insecure, I have done a little search but not found anything I can understand, can someone give me the basic details and if its really urgent I see to this, all the dhop told me was it would be round £170. Thanks