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Dorman M390121 New Brake Master Cylinder OE Replacement

(1987-1992 Volkswagen Jetta; 1990-1993 Volkswagen Passat GL; 1992 Volkswagen Passat CL; 1993-1994 Volkswagen Passat GLX + 4 more models)

Part of: Dorman Brake Master Cylinder Replacement

Other options in this family: Dorman M39298 Dorman M19012 Dorman M390139 Dorman M630735 Dorman M390200

Manufacturer

Picture for manufacturer Dorman

Part Number

M390121
7 reviews
Sale Price

$124.83

In Stock (5)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Dorman M390121 is a 100% new brake master cylinder engineered as a direct OE replacement. Unlike remanufactured units, this master cylinder is built entirely from new materials, delivering the reliability and safety you expect from a critical braking component.

Key Features:

  • Precise OE Replacement: Cylinder housing is constructed to match the casting material of the original part for consistent, OE-level braking performance
  • Durable EPDM Rubber Components: All internal rubber seals and components are made from high-quality EPDM compound, providing superior resistance to glycol-based brake fluids
  • 100% New Construction: Made entirely of new materials — not remanufactured — ensuring the highest standards of quality and safety
  • Meets SAE Standards: Manufactured to meet rigorous SAE International specifications for hydraulic brake system components
  • Direct-Fit Design: Engineered to match the design, function, and performance of the original master cylinder for a straightforward installation

The Dorman M390121 brake master cylinder is the trusted choice for repair professionals and DIY enthusiasts seeking a dependable, long-lasting replacement for a worn or failed OEM unit.

Products specifications

Fits

1987-1992 Volkswagen Jetta; 1990-1993 Volkswagen Passat GL; 1992 Volkswagen Passat CL; 1993-1994 Volkswagen Passat GLX; 1987-1992 Volkswagen Golf; 1987 Volkswagen Scirocco Base; 1987-1988 Volkswagen Scirocco 16-Valve; 1991-1994 Nissan Maxima

Feature - Benefit 1

Cylinder housing is constructed from high-quality cast iron or aluminum for long-lasting durability

Feature - Benefit 2

All rubber components are of high-quality EPDM compound for resistance to glycol-based brake fluid

Feature - Benefit 3

Direct replacement for a proper fit

Feature - Benefit 4

Manufactured to strict engineering quality standards, each Brake Master Cylinder meets S.A.E. specifications

Master Cylinder Material

Aluminum

Secondary Outlet Thread Diameter

10

Rearward Outlet Size

M10 X 1.0

Master Cylinder Bore Diameter

0.938

Mounting Hardware Included

No

Thread Pitch

1.0

Reservoir Included

Yes

Package Contents

Master Cylinder

Number of Outlets

4

Sensor Included

Yes

Primary Outlet Thread Pitch

1 mm

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