Dynamite Friction 631-31090L Disc Brake Rotor - Rear Left

Overview of the Dynamite Friction DFC Brake Rotor

The Dynamite Friction DFC Brake Rotor - Drilled and Slotted - Silver (part number 631-31090L) is engineered for BMW 135i and 135is models. This vented disc brake rotor features a directional, slotted, and drilled surface designed to enhance braking performance and heat dissipation.

• Compatible with BMW 135i and 135is
• Part Number: 631-31090L
• Directional drilled and slotted surface for improved brake pad bite
• Vented rotor design for efficient heat dissipation
• Rust-resistant zinc silver hat finish
• 5 bolt holes with 14.7 mm diameter and 120 mm bolt circle diameter
• Nominal thickness of 21.8 mm and discard thickness of 20.4 mm
• Overall diameter of 324 mm and height of 77.5 mm

Product Line Details: DFC Brake Rotor - Drilled and Slotted - Silver

The DFC Brake Rotor - Drilled and Slotted - Silver line by Dynamite Friction offers rotors with a combination of drilled holes and slots on the braking surface. This design helps to reduce brake fade by allowing gases and debris to escape, while the vented rotor construction improves cooling. The zinc silver coating on the rotor hat provides corrosion resistance, extending the rotor's service life. This product line is tailored for drivers seeking reliable braking performance with enhanced heat management.

Technical Specifications and Features

This disc brake rotor is vented, which means it has internal vanes between the two braking surfaces to improve airflow and cooling during operation. The rotor's surface is both drilled and slotted, arranged directionally to optimize water and gas evacuation. The rotor measures 324 mm in outside diameter with a height of 77.5 mm. It features five bolt holes with a diameter of 14.7 mm and a bolt circle diameter of 120 mm, matching the BMW 135i and 135is wheel hub specifications. The nominal thickness is 21.8 mm, with a discard thickness of 20.4 mm, ensuring safe replacement intervals. The rotor hat is finished with a rust-resistant zinc silver coating to protect against corrosion.

Common Applications and Problem Solving

• Replacement for worn or warped rotors on BMW 135i and 135is
• Improves braking consistency under high heat conditions
• Reduces brake fade during aggressive driving or track use
• Helps prevent rust and corrosion on rotor hats
• Enhances brake pad bite and water dispersion in wet conditions

Installation Notes and Tips

Ensure the rotor is compatible with your BMW 135i or 135is by verifying the part number 631-31090L. Clean the rotor surface before installation to remove any protective coatings or residues. Use proper torque specifications for the 5 lug bolts with 14.7 mm diameter and 120 mm bolt circle diameter. Check rotor thickness regularly and replace when thickness reaches the discard limit of 20.4 mm. Directional rotors must be installed following the indicated rotation direction for optimal performance.

Quality Assurance

Dynamite Friction manufactures the DFC Brake Rotor - Drilled and Slotted - Silver to meet OEM standards for fitment and performance. The rust-resistant coating on the rotor hat helps extend service life. While specific warranty details are not provided, this rotor is designed to maintain consistent braking performance and durability for BMW 135i and 135is vehicles when installed and maintained properly.