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Dorman M630389 Brake Master Cylinder Replacement

(Chevrolet S10 1987-93, Astro 1987-90, S10 Blazer 1987-88, Aveo 2004-08, Aveo5 2007-08, LLV 1990-93; GMC Sonoma 1991-93, Safari 1987-90 + 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

M630389
4 reviews
Sale Price

$134.23

In Stock (5)

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Usually delivered within 2 days

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No Hassle Returns

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Fitment guaranteed

Fitment guaranteed

Product Details

The Dorman M630389 is a 100% new brake master cylinder engineered as a direct OE replacement. Unlike remanufactured alternatives, this unit is built entirely from new components, ensuring consistent hydraulic performance and long-term reliability straight out of the box.

The cylinder housing is constructed to match the casting material of the original equipment part, preserving the same fit and structural integrity as the factory component. All internal rubber seals and components are manufactured from high-quality EPDM compound, providing superior resistance to glycol-based brake fluids and extending service life.

Key Features:

  • Precision-engineered replacement — matches the design, function, and performance of the original master cylinder
  • 100% new construction — not remanufactured; built from all-new materials for maximum safety and quality
  • EPDM rubber components — resistant to glycol-based brake fluids for lasting durability
  • OE-matched housing — cylinder casting material mirrors the original for proper fit and performance
  • SAE compliant — manufactured to meet rigorous SAE International standards

Dorman's brake master cylinders are designed for repair professionals and vehicle owners who demand a dependable, safety-critical replacement. This master cylinder restores proper brake pedal feel and hydraulic pressure to keep your braking system operating at full confidence.

Products specifications

Fits

Chevrolet S10 1987-93, Astro 1987-90, S10 Blazer 1987-88, Aveo 2004-08, Aveo5 2007-08, LLV 1990-93; GMC Sonoma 1991-93, Safari 1987-90, S15 1987-90, S15 Jimmy 1987-88; Pontiac G3 2007-08, Wave 2006-08

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

Master Cylinder Bore Diameter

0.875

Thread Pitch

1.0

Secondary Outlet Thread Diameter

10

Sensor Included

Yes

Mounting Hardware Included

No

Number of Outlets

2

Package Contents

Master Cylinder

Reservoir Included

Yes

Rearward Outlet Size

M10 X 1.0

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I placed an order on Sunday and received my order on Wednesday morning. Product was carefully packaged and as advertised. Will buy from Autoplicity again. Thanks for the great service. Order number #18578

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