One problem related to brake hoses, lines/piping, and fittings has been reported for the 2001 Nissan Frontier. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Nissan Frontier based on all problems reported for the 2001 Frontier.
Check brake light came on and stayed on. Brake line corroded to the extent that brake fluid leaked out and emptied the master cylinder. Could only stop if the master cylinder was constantly refilled. Master cylinder would empty as soon as the brake pedal was pushed.