The Dodge owner's manual does not specify brake fluid flushing intervals. This is similar to recommendations from Ford, Hyundai and Toyota. Chevrolet, however, calls for a brake fluid change every 45,000 miles, and Honda says to do it every three years regardless of the vehicle’s mileage. Three years is also the recommended interval for most Volkswagens, but Mercedes-Benz vehicles typically call for fresh fluid every two years or 20,000 miles. I think that it is good preventative maintenance to flush your Challenger's brake fluid every 30,000 miles. What do you do? Braking systems aren't indestructible. Parts, like the rubber in the valves in the master cylinder, calipers and wheel cylinders deteriorate. All the nasty little bits that flake off end up in your brake fluid. Plus, the fluid itself can get old and worn out. Moisture can also get in the system. That leads to rust, which leads to more nasty bits in your brake fluid. All this adds up to a brake system with compromised effectiveness and decreased stopping power. Think of it this way: You wouldn't skip changing your car's engine oil, right? It's the lifeblood of your engine, and when it gets contaminated by impurities, you put the entire engine at risk. It's the same with brake fluid. Let it get dirty and you won't be able to stop as well and you may be in for significant brake work expenses.
Another thought is that when the water in the brake fluid may flash-boil due to sudden temperature rise, such as in an emergency braking or long downhill braking situation, That is not going to help your brake soft parts, either. Considering how cheap it is and how easy it is to do, why would you not just bleed the brakes and put the good stuff in your brake and clutch system, and sidestep yet another potential problem? There are even kits to pump brake fluid UP from the calipers to the master cylinder if you mistrust the errant air bubbles that may hug the inside of the brake lines.
