{"product_id":"dorman-m390249-brake-master-cylinder","title":"Dorman M390249 Brake Master Cylinder","description":"\u003ch2\u003eReliable Brake Master Cylinder for Buick, Cadillac, and Chevrolet\u003c\/h2\u003e\u003cp\u003eThe Dorman M390249 Brake Master Cylinder is engineered to restore proper brake hydraulics in select Buick, Cadillac, and Chevrolet models. Designed with an aluminum body and an included reservoir, this master cylinder ensures consistent brake fluid delivery for safe and effective braking performance.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eConstructed from durable aluminum for corrosion resistance\u003c\/li\u003e\n\u003cli\u003eIncludes reservoir for brake fluid containment\u003c\/li\u003e\n\u003cli\u003eCompatible with Buick Caprice, Cadillac Fleetwood, and Chevrolet Roadmaster\u003c\/li\u003e\n\u003cli\u003eFeatures dual outlets with precise thread sizes (M11 x 1.5 rearward, M12 x 1.0 secondary)\u003c\/li\u003e\n\u003cli\u003eMaster cylinder bore diameter of 40 mm \u0026amp; 1-1\/8 inch for accurate hydraulic pressure\u003c\/li\u003e\n\u003cli\u003ePart number M390249 for exact replacement\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eProduct Details and Specifications\u003c\/h2\u003e\u003cp\u003eThis brake master cylinder is designed without mounting hardware, allowing for direct replacement using existing components. The aluminum construction provides strength and resistance to wear, while the included reservoir simplifies installation and maintenance. The unit features two outlets to accommodate brake line connections, with a rearward outlet size of M11 x 1.5 and a secondary outlet thread diameter of M12 x 1.0, both with a thread pitch of 1.0. The bore diameter measures 40 mm (1-1\/8 inch), ensuring compatibility with the hydraulic system requirements of the Buick Caprice, Cadillac Fleetwood, and Chevrolet Roadmaster.\u003c\/p\u003e\u003ch2\u003eCompatible Vehicles and Applications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eBuick Caprice brake system restoration\u003c\/li\u003e\n\u003cli\u003eCadillac Fleetwood hydraulic brake repairs\u003c\/li\u003e\n\u003cli\u003eChevrolet Roadmaster brake master cylinder replacement\u003c\/li\u003e\n\u003cli\u003eAddresses issues such as brake fluid leaks, spongy brake pedal, and loss of hydraulic pressure\u003c\/li\u003e\n\u003cli\u003eSuitable for vehicles requiring a 40 mm bore diameter master cylinder with dual outlets\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eInstallation Notes and Tips\u003c\/h2\u003e\u003cp\u003eInstallation requires removal of the existing master cylinder and proper connection of brake lines to the specified outlet threads. Since mounting hardware is not included, retain original mounting bolts and brackets. Bleed the brake system thoroughly after installation to remove air and ensure optimal brake performance. Verify thread sizes (M11 x 1.5 rearward and M12 x 1.0 secondary) before connecting brake lines to avoid cross-threading.\u003c\/p\u003e\u003ch2\u003eQuality Assurance and Warranty\u003c\/h2\u003e\u003cp\u003eDorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The M390249 Brake Master Cylinder undergoes rigorous quality control to ensure durability and reliable operation. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in material and workmanship.\u003c\/p\u003e","brand":"Dorman","offers":[{"title":"Default Title","offer_id":43792135651509,"sku":"BKKX-M390249","price":161.2,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/1442\/1173\/files\/DB_M390249_Fro.jpg?v=1774997561","url":"https:\/\/www.partcatalog.com\/products\/dorman-m390249-brake-master-cylinder","provider":"PartCatalog","version":"1.0","type":"link"}