What is the Difference Between Floating Disc and Fixed Disc?
2 Answers
Different braking principles and construction are the distinctions between floating brake discs and fixed brake discs. Below are the relevant introductions: Different braking principles: Floating brake discs slide freely on the axle pins matched with the bracket to generate braking torque; fixed brake discs generate friction and braking torque when the pistons inside the brake calipers extend the brake pads to clamp the brake disc. Different construction: The brake caliper of a floating brake disc is floating; the brake caliper of a fixed brake disc is fixed. The brake disc, also known as the brake, refers to the component that generates braking torque to hinder the movement or tendency of movement of the vehicle. Currently, friction brakes are widely used in automobiles, which utilize the friction between the fixed components and the working surface of the rotating components to generate braking torque. Depending on the installation position, brakes can be divided into wheel brakes and central brakes. Brakes with rotating components fixed on the wheels or half-shafts are called wheel brakes; brakes with rotating components fixed on the transmission shaft of the drivetrain are called central brakes. Wheel brakes are generally used for service braking and may also serve for emergency braking and parking braking; central brakes are usually only used for parking braking and retarder braking.
As a car enthusiast, I found the design of floating brake discs quite ingenious when disassembling the braking system. It allows slight movement of the disc, acting like a small buffer zone that absorbs thermal expansion and road vibrations, reducing brake squeal and deformation risks. In contrast, fixed discs are rigidly mounted as a single unit, offering simpler structure and lower cost, making them suitable for regular daily driving. However, during aggressive driving or heavy loads, fixed discs are prone to overheating and deformation, leading to brake fade, while floating discs maintain consistency, which is particularly helpful for high-speed cornering or mountain roads. Additionally, floating discs offer better wear resistance and longer lifespan, though maintenance is slightly more expensive, requiring precise alignment during replacement. Overall, the choice depends on your driving habits: fixed discs are sufficient for city commuting; if you frequently race or tow heavy loads, floating discs provide better safety and stability. This design difference is also noticeable during routine inspections - floating discs often have small gaps, while fixed discs are compact and integrated.
