Dorman Brake Master Cylinder (MPN: M39578)

High-quality OE replacement with durable construction and precise fit.

The Dorman Brake Master Cylinder is designed as an OE replacement component, ensuring compatibility and reliability for various vehicle applications. With a bore diameter of 1.125 inches and 1.578 inches, this master cylinder is engineered to meet strict S.A.E. specifications, providing a dependable solution for your braking system needs. Constructed from high-quality cast iron or aluminum, it offers long-lasting durability and resistance to wear under demanding conditions.

This brake master cylinder features all rubber components made from high-quality EPDM compound, which is resistant to glycol-based brake fluid, enhancing the overall longevity of the product. The inclusion of a reservoir ensures that the system maintains optimal fluid levels for effective braking performance. Each unit is manufactured to strict engineering quality standards, making it a direct replacement that guarantees a proper fit and function.

Features

• Cylinder Housing Is Constructed From High-Quality Cast Iron Or Aluminum For Long-Lasting Durability
• All Rubber Components Are Of High-Quality EPDM Compound For Resistance To Glycol-Based Brake Fluid
• Manufactured To Strict Engineering Quality Standards, Each Brake Master Cylinder Meets S.A.E. Specifications
• Direct Replacement For A Proper Fit

Specifications

• Manufacturer: Dorman
• Manufacturer Part Number: M39578
• Condition: New
• Bore Diameter: 1-1/8 Inch And 1.578 Inch
• Port Size: 9/16 Inch-18 Forward Port And 1/2 Inch-20 Rearward Port
• Finish: OEM
• Color: Gray
• Material: Aluminum
• Includes Reservoir: Yes

Compatibility / Fit

• 1985-1989 Chevrolet Astro
• 1991-1993 Chevrolet Astro
• 1985-1995 Chevrolet G10
• 1978-1978 Chevrolet G20
• 1985-1995 Chevrolet G20
• 1985-1989 Chevrolet P20
• 1985-1995 GMC G1500
• 1985-1995 GMC G2500
• 1985-1989 GMC P2500
• 1985-1993 GMC Safari

Technical Documents

• m39578_brakeMasterbleeding.pdf
• brakemastercylinder_is.pdf