The fault was detected after a number of customers reported a softness in the brake pedal which was traced to the hydraulics. Ford engineers suspect that in affected models, the brake fluid has become contaminated by small quantities of mineral oil used in the manufacture of the clutch hoses, which can deform the system's seals.
The manufacturer is asking all owners to return vehicles to their local dealers who will carry out an inspection and remedial work free of charge. As a precaution, dealers will fit new clutch hoses and brake seals and flush the hydraulic system with new brake fluid - a procedure taking between two and four hours. Further information is available from the Ford customer enquiry line on 0800 400415.