Square O-Ring Kit - 1.75

The Wilwood Square O-Ring Kit - 1.75 is a precision brake caliper rebuild component designed for mechanics and performance enthusiasts maintaining or restoring Wilwood brake systems. This o-ring kit contains the elastomer seals necessary to restore hydraulic integrity and prevent fluid weeping in brake calipers equipped with 1.75-inch pistons. Whether you're performing routine caliper maintenance, addressing seal degradation, or completing a full brake system restoration, this kit provides the OEM-specification replacements needed for reliable stopping power.

Square o-rings serve as dynamic seals within brake caliper bores, creating the hydraulic barrier that prevents pressurized brake fluid from escaping past the piston during system operation. The 1.75-inch specification matches Wilwood piston diameters commonly found in road-course, street performance, and drag racing brake packages. Wilwood's engineered elastomer formulation resists thermal cycling, maintains elasticity across temperature extremes, and withstands the chemical exposure inherent to modern brake fluids. Proper o-ring replacement during caliper service is critical—aged or compromised seals allow internal leakage, fluid loss, and eventual brake fade or complete caliper failure.

This kit is essential for shops and DIY mechanics rebuilding Wilwood brake calipers as part of preventive maintenance or after caliper disassembly. Professional brake technicians routinely replace o-rings during caliper overhaul to ensure long-term seal integrity and eliminate the risk of fluid weepage. Compatible with Wilwood four-piston, six-piston, and multi-piston caliper designs featuring 1.75-inch bore pistons, the kit delivers OEM-quality performance at a fraction of complete caliper replacement cost. Installation requires basic caliper disassembly, cleaning, and reassembly—standard procedure for any serious brake work.