Confirm the axle mounts match a disc setup, then plan on two brake hoses, a master cylinder, combination valve, two steel lines, and new parking brake cables. Do not attempt the conversion if the car has ABS. Prefer factory disc components from a disc-equipped Cougar rather than an aftermarket kit so rear brake bias does not increase too much.
The owner of a 2002 Mercury Cougar V6 with rear drums wants to convert them to disc brakes. The expert says to verify the axle mounts, replace the hoses, master cylinder, combination valve, steel lines, and parking brake cables, and abandon the idea if the car has ABS. Another reply notes that some 2002 Cougars had rear discs and recommends using stock disc parts rather than an aftermarket kit.
