Dynamite Friction 631-31048L Disc Brake Rotor - Front Left

Overview of the DFC Brake Rotor - Drilled and Slotted - Silver

The Dynamite Friction DFC Brake Rotor - Drilled and Slotted - Silver (part number 631-31048L) is engineered for BMW 330Ci, 330i, 330xi, and Z4 models. This vented disc brake rotor combines drilled and slotted surface features with a rust-resistant zinc silver hat finish to support reliable braking performance.

• Compatible with BMW 330Ci, 330i, 330xi, and Z4 models
• Part number: 631-31048L
• Vented disc brake rotor with drilled and slotted surface
• Nominal thickness: 25 mm; discard thickness: 23.4 mm
• Overall height: 52.7 mm; outside diameter: 325 mm
• 5 bolt holes with 14.6 mm diameter and 120 mm bolt circle diameter
• Directional brake surface design for optimized heat dissipation
• Rust-resistant zinc silver hat finish and plain disc finish

Detailed Product Description

The DFC Brake Rotor - Drilled and Slotted - Silver from Dynamite Friction is designed specifically for select BMW models including the 330Ci, 330i, 330xi, and Z4. This rotor features a vented design that improves heat dissipation during braking, reducing the risk of brake fade under demanding conditions. The surface is both drilled and slotted, which helps to evacuate gases, dust, and water, maintaining consistent brake pad contact and performance.

With a nominal thickness of 25 mm and a discard thickness of 23.4 mm, this rotor ensures durability and safety by indicating when replacement is necessary. The rotor’s overall height is 52.7 mm with an outside diameter of 325 mm, matching OEM specifications for proper fitment. The 5 bolt holes, each 14.6 mm in diameter, are arranged on a 120 mm bolt circle diameter, ensuring secure mounting.

The rotor’s hat is finished with a zinc silver coating that provides rust resistance, extending the rotor’s service life. The plain disc finish combined with the directional drilled and slotted surface supports effective braking performance and heat management.

About the DFC Brake Rotor - Drilled and Slotted - Silver Product Line

The DFC Brake Rotor - Drilled and Slotted - Silver line by Dynamite Friction focuses on rotors that combine drilled holes and slots to enhance braking efficiency and rotor cooling. This product line is designed to meet the demands of performance-oriented vehicles like the BMW 3 Series and Z4, offering a balance of durability and improved brake response. The silver zinc coating on the hat provides corrosion resistance, which is critical for maintaining rotor integrity over time.

Common Applications and Problem Solving

• Replacement for worn or warped rotors on BMW 330Ci, 330i, 330xi, and Z4
• Improves heat dissipation to reduce brake fade during aggressive driving
• Helps eliminate brake noise and vibration caused by uneven rotor surfaces
• Prevents rust and corrosion buildup on rotor hats for longer service life
• Maintains consistent braking performance in wet or dusty conditions

Installation Notes and Tips

• Ensure rotor thickness is above discard thickness (23.4 mm) before installation
• Clean mounting surface and hub to prevent rotor runout
• Torque bolts to manufacturer specifications using the 5-bolt pattern (120 mm bolt circle diameter)
• Check brake pads for wear and replace if necessary to ensure optimal rotor performance
• Perform a bed-in procedure after installation to maximize braking efficiency

Quality Assurance and Warranty

Dynamite Friction manufactures the 631-31048L rotor to meet or exceed OEM standards for fit, form, and function. The rust-resistant zinc silver hat finish and vented design contribute to the rotor’s durability and performance. While specific warranty details are not provided, Dynamite Friction products typically come with a limited warranty against defects in materials and workmanship. Always verify warranty terms with the supplier or manufacturer.