Centric 121.66039 Disc Brake Rotor - Rear

Reliable Disc Brake Rotor for Chevrolet and GMC Vehicles

The Centric C-TEK Standard Disc Brake Rotor 121.66039 is engineered to provide consistent braking performance for Chevrolet Blazer, GMC Jimmy, and Sonoma models. Designed with precision, this vented rotor ensures effective heat dissipation and durability under demanding driving conditions.

• Part Number: 121.66039
• Compatible with Chevrolet Blazer, GMC Jimmy, and Sonoma
• Vented disc brake rotor with smooth surface finish
• Outside diameter: 11.614 inches (295 mm)
• Nominal thickness: 0.787 inches (20.000 mm)
• Discard thickness: 0.728 inches (18.500 mm)
• Overall height: 2.874 inches (73.000 mm)
• 5 lug holes with 0.516 inch (13.100 mm) diameter
• Center hole diameter: 2.783 inches (70.700 mm)
• Mounting bolt hole circle diameter: 120.700 mm (4.752 inches)
• Weight: 14 lbs (6.360 kgs)
• ABS tone ring not included
• Floating center mounting design with straight vane style

About the C-TEK Standard Disc Brake Rotors Line

The C-TEK Standard Disc Brake Rotors line by Centric offers a balance of quality and value for standard braking applications. These rotors are designed to meet or exceed OEM specifications, providing reliable stopping power and consistent performance. The 121.66039 rotor features a vented design to improve heat dissipation, which helps reduce brake fade during extended use on Chevrolet Blazer, GMC Jimmy, and Sonoma vehicles.

Technical Details and Performance

This vented disc brake rotor has a smooth surface type that ensures even pad contact and wear. The nominal thickness of 0.787 inches (20.000 mm) and discard thickness of 0.728 inches (18.500 mm) define the usable rotor life before replacement is necessary. The rotor’s overall height of 2.874 inches (73.000 mm) and outside diameter of 11.614 inches (295 mm) are engineered for precise fitment and optimal braking efficiency. The floating center mounting design and straight vane style enhance rotor cooling and structural integrity.

Common Applications and Problem Solving

• Replacement for worn or warped rotors causing brake pulsation
• Addressing reduced braking performance due to rotor thickness below discard limits
• Eliminating noise and vibration from uneven rotor surfaces
• Improving heat dissipation to prevent brake fade on Chevrolet Blazer, GMC Jimmy, and Sonoma
• Upgrading from solid to vented rotors for better thermal management

Installation Notes and Tips

Ensure the rotor thickness is measured before installation to confirm it meets nominal specifications. Clean the rotor surface to remove any protective coatings or contaminants. Verify the mounting bolt hole circle diameter and lug hole dimensions match the vehicle hub. Since this rotor does not include bearings or an ABS tone ring, reuse existing components if applicable. Proper torque specifications should be followed when securing the rotor to avoid warping.

Quality Assurance and Warranty

Centric’s C-TEK Standard Disc Brake Rotors are manufactured to meet OEM standards for fit, form, and function. Each rotor undergoes quality control inspections to ensure dimensional accuracy and material integrity. While specific warranty details are not provided here, Centric typically offers coverage against defects in materials and workmanship. Refer to Centric’s official documentation for complete warranty information.