{"product_id":"dorman-m630556-brake-master-cylinder","title":"Dorman M630556 Brake Master Cylinder","description":"\u003ch2\u003eReliable Brake Master Cylinder for Chevrolet and GMC Trucks\u003c\/h2\u003e\u003cp\u003eThe Dorman M630556 Brake Master Cylinder is engineered to restore proper brake hydraulics for select Chevrolet and GMC heavy-duty trucks. Designed with an aluminum body and integrated reservoir, this master cylinder ensures consistent brake fluid delivery and reliable stopping power for your Express, Savana, Sierra, Silverado, Suburban, and Yukon XL 2500 series vehicles.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eMaster cylinder bore diameter: 1.5 inches for precise hydraulic pressure\u003c\/li\u003e\n\u003cli\u003eDurable aluminum construction for corrosion resistance and longevity\u003c\/li\u003e\n\u003cli\u003eIncludes reservoir for brake fluid storage and management\u003c\/li\u003e\n\u003cli\u003eEquipped with sensor to monitor brake system status\u003c\/li\u003e\n\u003cli\u003eTwo outlet ports with rearward outlet thread size M14 x 1.5\u003c\/li\u003e\n\u003cli\u003eCompatible with Chevrolet Express 2500\/3500, GMC Savana 2500\/3500, Sierra 2500 HD\/3500 HD, Silverado 2500\/2500 HD\/3500 HD, Suburban 2500, and Yukon XL 2500\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eProduct Details and Specifications\u003c\/h2\u003e\u003cp\u003eThe Dorman M630556 master cylinder features a 1.5-inch bore diameter, which is critical for maintaining the correct hydraulic pressure in the brake system. Constructed from aluminum, this part offers enhanced resistance to corrosion compared to traditional cast iron units, contributing to longer service life. The included reservoir simplifies installation and ensures proper brake fluid containment. Additionally, the master cylinder comes with a sensor to provide real-time feedback on brake system performance. It has two outlets, with the secondary outlet thread diameter measuring 14 mm and a thread pitch of 1.5, matching OEM specifications for a secure fit. Note that mounting hardware is not included with this part.\u003c\/p\u003e\u003ch2\u003eCompatible Vehicles and Applications\u003c\/h2\u003e\u003cp\u003eThis master cylinder is compatible with a range of Chevrolet and GMC heavy-duty trucks, including:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eChevrolet Express 2500 and 3500\u003c\/li\u003e\n\u003cli\u003eGMC Savana 2500 and 3500\u003c\/li\u003e\n\u003cli\u003eGMC Sierra 2500 HD and 3500 HD\u003c\/li\u003e\n\u003cli\u003eChevrolet Silverado 2500, 2500 HD, and 3500 HD\u003c\/li\u003e\n\u003cli\u003eChevrolet Suburban 2500\u003c\/li\u003e\n\u003cli\u003eGMC Yukon XL 2500\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCommon Issues Addressed by This Master Cylinder\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eSpongy or unresponsive brake pedal\u003c\/li\u003e\n\u003cli\u003eBrake fluid leaks from the master cylinder or reservoir\u003c\/li\u003e\n\u003cli\u003eBrake warning light activation due to sensor faults\u003c\/li\u003e\n\u003cli\u003eReduced braking efficiency or inconsistent brake pressure\u003c\/li\u003e\n\u003cli\u003eContaminated or deteriorated brake fluid reservoir\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eInstallation Notes and Tips\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eEnsure the brake system is properly bled after installation to remove air pockets\u003c\/li\u003e\n\u003cli\u003eVerify thread pitch and outlet sizes match your vehicle’s brake lines (M14 x 1.5 rearward outlet)\u003c\/li\u003e\n\u003cli\u003eUse OEM or compatible brake fluid to maintain system integrity\u003c\/li\u003e\n\u003cli\u003eCheck sensor connections for proper operation before completing installation\u003c\/li\u003e\n\u003cli\u003eMounting hardware is not included; reuse existing hardware or source separately\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eQuality Assurance and Warranty\u003c\/h2\u003e\u003cp\u003eDorman manufactures this brake master cylinder to meet or exceed OEM standards for fit, form, and function. The aluminum construction and integrated sensor contribute to reliable brake system performance. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in materials and workmanship. Refer to Dorman’s official documentation for exact warranty terms.\u003c\/p\u003e","brand":"Dorman","offers":[{"title":"Default Title","offer_id":43792318169269,"sku":"BKKX-M630556","price":128.63,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/1442\/1173\/files\/DB_M630556_Generic_384fcd5e-d452-4b49-ad73-907650389106.jpg?v=1774997707","url":"https:\/\/www.partcatalog.com\/products\/dorman-m630556-brake-master-cylinder","provider":"PartCatalog","version":"1.0","type":"link"}