Wilwood 120-10525-P D8-4 Front Disc Brake Caliper 4-Piston Polished Aluminum

The Wilwood 120-10525-P is a D8-4 front disc brake caliper featuring a polished finish and engineered as a direct bolt-on upgrade over the factory original cast iron calipers. Built from a forged billet aluminum body, this caliper delivers a significant weight reduction over the OEM unit while providing superior rigidity and long-term durability.

Constructed using Wilwood's in-house FEA (Finite Element Analysis) design and 3-D modeling technology, the D8-4 mounts in the stock location over stock rotors and accepts the original-style D8 brake pads — no brackets or adapters required. Piston sizing matches the factory caliper exactly, so pedal travel, master cylinder output, and front-to-rear brake bias remain unchanged. The only hardware modification required is a new flex line with a 1/8"-27 NPT end to accommodate the aluminum caliper body.

Key Features:

• Forged billet aluminum body — increased strength with significant weight savings over cast iron
• 4-piston design with 1.88" stainless steel pistons for corrosion resistance and consistent clamping force
• 1.25" rotor compatibility — fits stock rotors with no modifications
• Square-cut O-ring seals retained in the bore by a groove in the caliper body for reliable sealing
• Stainless steel bridge wear plates protect the caliper body from pad backing plate contact
• High-temperature seals eliminate the seal failures common in original cast iron designs
• Polished finish for a clean, show-quality appearance through open-spoke wheels
• Fits inside 1967 and later production steel rally wheels and most later-model alloy wheels
• Original 1965–66 steel "JK" code wheels and some aftermarket alloy replicas may require a 3/16" or thicker wheel spacer for clearance
• Uses common D8 brake pads — widely available replacement pads

The D8-4 generates positive pedal response and high clamping efficiency, making it an ideal performance upgrade that retains OEM-style installation simplicity. Sold individually.