Classic/Antique Car Repair: Brake failure, classic car collector, brake caliper

Question
QUESTION: Hello,

A friend of mine is a classic car collector and has has the following occur:

While driving his car around the area he experienced an occurance of brake failure. He stated the brakes had been working fine most of the day. However, after driving a little longer distance, the brake pedal went to the floor and brake failure occurred. He called AAA and they got him home.

Assuming it was the Master, he purchased a new unit from NAPA. Upon install completion, all seemed well. The following day he drove the car to work once again. No issues until the car had run a longer distance on one leg of his travel.

He noted and conveyed to me that the fluid level was correct, there are no hydraulic leaks, and the system was bleed properly. He also noted that when he used the park brake to slow the vehicle it was very weak. Another strange anomaly is that the next day with no further repairs, the brakes seemed to be fine.

This leads me in the direction of brake fade. If the rear brakes are not pulling their weight, it seems plausible that the from discs/pads  could be heating to the point of failure/reduced friction efficiency.

What are you thoughts?

ANSWER: The year and make of the car would help a lot here please. let me know.

---------- FOLLOW-UP ----------

QUESTION: It's a 65 Ford Thunderbird. Thanks for the reply.

Answer
Ok, so it has disc brakes on the front and drum bakes on the rear. The first thing that I would check is a sticking brake caliper  that is causing one or both front brakes to over heat This boils the brake fluid after driving a while and no brakes. If that is not it let me know and we will go to the next step.
Brad