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Dorman M630671 Brake Master Cylinder OE Replacement

(GMC G2500 1979-84, K1500 1979-84, C1500 1979-84, K2500 1979-86, Jimmy 1978-82, C3500 1979-86, K2500 Suburban 1979-82, 1984, K3500 1979-86 + 58 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

M630671
12 reviews
Sale Price

$143.46

In Stock (5)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Dorman M630671 is a 100% new, direct-fit replacement brake master cylinder engineered to restore proper hydraulic braking function. Designed as a precise OEM-equivalent replacement, this master cylinder matches the design, dimensions, and performance characteristics of the original factory unit.

Unlike remanufactured alternatives, this unit is built entirely from new components, ensuring consistent quality and long-term reliability right out of the box. The cylinder housing is cast to match the original part's material composition, while all internal rubber components are manufactured from high-grade EPDM compound, providing excellent resistance to glycol-based brake fluids.

Key Features:

  • Precise OE Replacement — Cylinder housing casting material matches the original part for accurate fit and similar performance
  • EPDM Rubber Components — All seals and rubber parts are made from high-quality EPDM compound, resistant to glycol-based brake fluid degradation
  • 100% New Construction — Built entirely from new materials, not remanufactured, for maximum safety and reliability
  • SAE Compliant — Manufactured to meet rigorous SAE International standards
  • Direct Bolt-On Fit — Engineered to match factory specifications for a straightforward installation

The Dorman M630671 brake master cylinder is a trusted solution for restoring full braking performance with a part that meets or exceeds original equipment standards.

Products specifications

Fits

GMC G2500 1979-84, K1500 1979-84, C1500 1979-84, K2500 1979-86, Jimmy 1978-82, C3500 1979-86, K2500 Suburban 1979-82, 1984, K3500 1979-86, C2500 1979-86, K1500 Suburban 1979-80, C1500 Suburban 1979-80, P3500 1979-89, C15 1978 + 53 more models

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

Reservoir Included

No

Secondary Outlet Thread Diameter

M12 X 1.0

Master Cylinder Bore Diameter

1.063

Master Cylinder Material

Aluminum

Thread Pitch

1.0

Sensor Included

No

Rearward Outlet Size

M12 X 1.0

Number of Outlets

2

Package Contents

Master Cylinder

Mounting Hardware Included

No

very good price fast shipping

fast ordering

Very fast process.

Ok so far

Great. I need this item shipped to an address other than my confirmed paypal address. I need it shipped to BFNY Performance 9515 Detroit Rd. Cleveland, Ohio 44102 Phone 440-787-7235 ^^^ SEE ABOVE NOTE When checking out it wouldn't let me change the shi

Fast process

great buying experience

Wow that was fast. I ordered a Pertronix Ignitor conversion kit. Not only were they by far the lowest price I could find, they shipped within hours of submitting the order. I got the shipment in less than 24 hrs, even though I ordered ground shipping. I was a little bummed that they did not offer free shipping, as I am used to with other online places, but with their fast turnaround, I am not begrudging it. Sure it might have been because they have a warehouse nearby, but it was still unexpectedly impressive. The part arrived and looks like it all there and should be good to go. <br><br>I can't vouch for their customer service, but so far I am pleasantly surprised.

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no place to put discount shipping code

This was my first order with Autoplicity. Their prices were great, and the ordering process very easy. I was a little frustrated at first, as the order didn't arrive as expected. When I called, it took a little work, but I finally got the info that it was shipping from the manufacturer, and did get the tracking info. The parts arrived when tracking said it should. Would I place another order with Autoplicity? Short answer is yes!

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