Maintain proper performance of the braking system in your 1989-1993 Dodge 5.9L Diesel with new brake fluid. Several manufacturers advise replacing the brake fluid every two to three years or at specific mileage intervals. Both regularly testing your brake fluid and replacing it at the manufacturer's recommended maintenance schedule are crucial to maintaining your brake system's performance. There are many brake fluids available such as DOT 3, DOT 4, DOT 5, and DOT 5.1. The most widely utilized braking fluids are DOT 3 and DOT 4. While DOT 3 and DOT 4 brake fluids are interchangeable, DOT 4 has a higher boiling point. Despite the fact the brakes are one of the most crucial safety features of a vehicle, brake fluid is one of the most overlooked fluids when it comes to routine maintenance. Brake fluid will eventually start to accumulate moisture despite being a closed system. As a result of the water's lowered boiling point, the braking efficiency will start to deteriorate. Shop XDP for all the leading producers of brake fluid including Lucas Oil, and more!