A-Premium Brake Master Cylinder Assembly for Chevy/GMC/Cadillac 2009-2014 — 1.25" Bore, Integrated Reservoir & Sensor

The A-Premium Brake Master Cylinder assembly is a direct-replacement aluminum master cylinder with integrated reservoir and sensor engineered to fit select Chevy, GMC and Cadillac trucks and SUVs from 2009–2014.

This complete master cylinder package arrives pre-assembled with the reservoir and brake fluid sensor installed, making it a practical swap for models that require the JL4/JD9 RPO configurations or comparable brake-control setups. Built from 101 aluminum alloy and delivered new in box, it includes the correct bore size and outlet thread specifications to match factory brake line connections for many Silverado, Sierra, Tahoe, Yukon and Escalade variants.

Which vehicles will this master cylinder fit?

The unit is designed for a family of full-size GM trucks and SUVs. Fitment covers Cadillac Escalade, Escalade ESV and EXT; Chevrolet Avalanche, Silverado 1500, Suburban and Tahoe; and GMC Sierra 1500, Yukon and Yukon XL from model years 2009–2014 when matched to the listed RPO codes.

• Cadillac Escalade 2009–2014, Escalade EXT/ESV where applicable
• Chevrolet Silverado/Sierra 1500 2009–2014 (JL4 active brake control or JD9 noted fit)
• Chevy Avalanche, Suburban, Tahoe 2009–2014; GMC Yukon/Yukon XL 2009–2014

What are the key technical specifications I should check?

Verify compatibility by comparing bore diameter, outlet thread sizes and the presence of the factory-style reservoir and sensor. This A-Premium assembly uses a 1.25-inch bore and M14 x 1.5 outlets for both rearward and secondary connections to align with OEM brake plumbing.

• Bore diameter: 1.25 inch for correct piston travel and pressure generation
• Outlet thread sizes: Rearward M14 x 1.5 and secondary M14 x 1.5
• Material: Aluminum Alloys 101 for strength and corrosion resistance
• Includes pre-installed reservoir and fluid-level sensor for plug-and-play replacement

How difficult is installation and what comes in the box?

The master cylinder ships as a ready-to-install assembly to streamline replacement. Basic mechanical skill and common shop tools are required; bleeding the brake system after installation is necessary to remove air and restore pedal feel.

• Package includes one brake master cylinder, reservoir, and sensor in a protective box
• New condition unit reduces prep work—no separate reservoir or sensor sourcing needed
• Expect standard brake-bleeding procedures after installation to ensure proper operation

What warranty and assurance come with this part?

A-Premium backs this brake master cylinder assembly with a one-year unlimited-mileage guarantee, offering coverage for defects in workmanship or materials under normal use. The warranty aims to provide confidence for DIY installers and professional technicians alike.

• One-year unlimited-mileage guarantee from A-Premium
• New, boxed condition and factory-quality construction
• Manufactured from durable 101 aluminum alloy to resist corrosion

Who is this for: This A-Premium master cylinder assembly is intended for owners and mechanics of 2009–2014 GM full-size trucks and SUVs who need a direct-replacement master cylinder with integrated reservoir and sensor. It’s a practical choice when matching RPO codes and thread/bore specifications is essential, and for anyone seeking a complete, ready-to-install unit backed by a one-year guarantee.