No. This is going to come as a shock, but the ONLY proper repair is to replace every part that has rubber that contacts the brake fluid. This is a really serious problem and there is no shortcut. Experienced mechanics will wash their hands with soap and water before using their fingertips to push the rubber bladder seal back into the master cylinder reservoir cap. They don't want fingerprint grease or any oil residue on their fingers to get in the fluid.
The parts that must be replaced are the master cylinder, front calipers, rear wheel cylinders, three rubber flex hoses, and the combination valve under the master cylinder. Many trucks also have a height-sensing proportioning valve attached to the rear axle. That has rubber o-rings so it has to be replaced too. Those parts must be removed first, then all the steel lines must be flushed and dried, then the new parts can be installed. If any part with rubber is not replaced, the contamination is going to leach out of it and recontaminate the entire system again.
If you look at that bladder seal under the reservoir cap, you'll see it is blown up and mushy. That is what has happened to all the other rubber seals and hoses. The lip seals in the master cylinder grow past the fluid return ports and block them. The typical symptom is dragging front brakes that get real hot. As the brake fluid heats up, it expands but it is blocked from flowing back up to the reservoir. The more it expands, the more the brakes self-apply, and the hotter they get.
Please believe me that you can not leave any rubber part in the system. People have tried and it always results in a brake system that doesn't work properly.
Sunday, February 9th, 2014 AT 10:30 PM