ACDelco 18A2820B Fully Coated Rear Solid Disc Brake Rotor

The ACDelco 18A2820B is a fully coated rear disc brake rotor engineered to deliver reliable, consistent braking performance. Built from G3000-grade cast iron and meeting SAE standards for structural integrity, this solid, non-vented rotor is a direct OE-quality replacement that installs ready-to-use with no machining required.

The rust-preventative coating provides corrosion protection across the entire rotor surface — including the hat and non-swept areas — helping to extend service life and maintain clean, professional appearance. Thickness variation is held to less than 0.0004 inches, minimizing pedal pulsation, brake noise, and uneven pad wear.

Key Features:

• Fully coated construction for superior corrosion resistance and long-term durability
• G3000 qualified cast iron material meets SAE structural integrity standards
• Solid (non-vented) rotor design with non-directional brake surface
• Thickness variation under 0.0004 in. minimizes pedal pulsation and noise
• Independently tested for NVH (Noise, Vibration, and Harshness) and durability
• Inspected for balance to ensure smooth brake operation
• No machining required — ready to install out of the box
• ABS tone ring not included
• Sold individually (1 per pack)

Specifications:

• Position: Rear
• Rotor Style: Solid (Non-Vented)
• Rotor Construction: 1-Piece, Full Cast
• Outside Diameter: 11.18 in. (284 mm)
• Nominal Thickness: 0.394 in. (10.0 mm)
• Discard Thickness: 0.331 in. (8.4 mm)
• Overall Height: 2.2 in. (55.4 mm)
• Center Bore Diameter: 3.0 in. (76 mm)
• Bolt Circle Diameter: 4.5 in. (114.3 mm)
• Bolt Hole Quantity: 5
• Pad Contact Surface Width: 1.9 in. (49.35 mm)
• OEM Part Number: 88878108

The ACDelco 18A2820B is the Gold-tier, fully coated variant in the 18A2820 rotor family, offering enhanced protection compared to uncoated versions. It is the ideal choice for drivers seeking OE-matched quality and lasting corrosion resistance.