Replace Master Cylinder and Brake Booster At Same Time?

I will take another slower, more detailed look tonight. I did a quick look at the flexible lines that connect to each caliper last night, and did not see any leakage. The brake line connection area of the master cylinder looked wet, that is what got me considering it to be a master cylinder problem. That and the popping sound seemed to come from right under the hood.

You are right about the replacing the whole van comment. I am going to take a second look tonight to see if I can locate the leak. Besides this latest brake episode, I need to replace a passenger side lower control arm, and inner and outer tie-rod ends on both sides.. That, and I have an oil leak to track down. It is our "utility" vehicle for taking yard waste to the recycling center, materials from lumberyard, etc. I am thinking of searching for another van to use for those types of tasks, but one that has around 100,000 miles on it. I applaud some of the really high mileage van owners on this site. They really must stay on top of their vehicle maintenance to have a high mileage vehicle that is dependable.

OK, these are the primary and secondary lines from the master cylinder to the hydraulic control unit. Has anyone replaced just these lines before? If so, do you have any advice?