Dorman 42074 Brake Master Cylinder Reservoir Cap Gasket

Brake Master Cylinder Reservoir Cap Gasket

Dorman 42074 is a rubber brake master cylinder reservoir cap gasket built to match the fit and function of the original gasket on specified vehicles. It is made for durable sealing performance in brake master cylinder reservoir applications, helping maintain a proper seal where the cap meets the reservoir.

Compatible With classic Chevrolet, GMC, Buick, Oldsmobile, Pontiac, and Cadillac brake systems, including many Chevrolet C10, K10, K5 Blazer, and GMC Jimmy applications. This Dorman 42074 gasket is also a direct replacement for interchange part number 409353.

Key Features

• Rubber construction for sealing performance in brake reservoir applications
• Matches the fit and function of the original master cylinder reservoir cap gasket
• Engineered for durability and reliable performance
• Designed for specified Chevrolet, GMC, Buick, Oldsmobile, Pontiac, and Cadillac vehicles
• OE-style replacement for brake master cylinder reservoir service

Detailed Description

This brake master cylinder reservoir cap gasket is used to restore the seal between the reservoir cap and the master cylinder reservoir. On vehicles such as the Chevrolet C10, K10, K5 Blazer, GMC Jimmy, and related full-size GM platforms, a worn or damaged gasket can allow fluid seepage, contamination, or loss of reservoir sealing integrity. Dorman 42074 provides a direct-fit replacement for the original gasket design on listed applications, with rubber material selected for dependable sealing in brake system service.

Fits 1983-1986 Chevrolet C10, N/A; Fits 1985-1986 Chevrolet K10, N/A; Fits 1985-1986 Chevrolet K5 Blazer, N/A; Fits 1985-1991 GMC Jimmy, N/A. Fits 1971-1975 Chevrolet Caprice, N/A; Fits 1971-1975 Pontiac Bonneville, N/A; Fits 1981-1985 Cadillac DeVille, N/A.

What It Helps Fix

• Brake fluid seepage around the master cylinder reservoir cap
• Loss of sealing at the reservoir opening
• Contamination entering the brake fluid reservoir
• Cracked, hardened, or flattened original gasket material
• Service issues during master cylinder cap removal and reassembly

Installation Notes and Tips

Inspect the reservoir cap and master cylinder sealing surface before installation. Clean away old fluid residue, dirt, and debris so the new gasket seats evenly. Verify application details by year, make, model, brake configuration, and notes such as Bendix brakes or rear brake size before ordering. Dorman 42074 is a direct replacement gasket for the listed vehicles and should be installed on a clean, dry sealing surface.

Quality Assurance

Dorman designs this gasket to match original fit and function on specified vehicles and builds it for durable, reliable service. The part number is 42074.