One problem related to brake fluid leak has been reported for the 1998 Ford Ranger. The most recently reported issues are listed below.
My 1998 Ford Ranger XLT so far had 2 complete brake failures due to corroded brake lines. This is a systemic problem caused by the spiral protection of the brake lines which keeps the humidity trapped and thus corrodes the lines. When this happens, brake fluid is leaking out when the pedal is pushed down yet no brake function is experienced. As this problem has a clear technical reason in the form of the brake lines, it is systemic in all such vehicles. This has been confirmed by my car mechanic shop which is frequently repairing Ford vehicles with this problem. The problem has no early warning indication and is not detected by the yearly inspection.