A-Premium Brake Master Cylinder Assembly for 2007–2008 GM Trucks & SUVs — Aluminum Bore, Reservoir & Sensor

This A-Premium Brake Master Cylinder is a complete replacement assembly—aluminum bore, integrated reservoir, and sensor—designed to restore brake fluid pressure and reservoir monitoring for select 2007–2008 GM trucks and SUVs.

When a worn or leaking master cylinder causes spongy pedal feel, low brake fluid warnings, or fluid loss, a full, factory-style replacement assembly can return reliable braking function. This unit from A-Premium arrives new, pre-assembled with the plastic reservoir and sensor fitted, and is engineered to match OE connection threads and bore size so it installs with minimal modification.

Will this master cylinder fit my vehicle?

Compatibility is focused on specific GM models from 2007–2008. Check your vehicle’s model, year and whether it has Active Brake Control (RPO JL4) or not—fitment varies by trim and axle configuration.

• Compatible with Cadillac Escalade/Escalade ESV/Escalade EXT (2007–2008).
• Fits Chevrolet Avalanche (2007–2008), Silverado 1500 LT/LTZ/WT (2007–2008) with RPO JL4 for some model years.
• Compatible with Suburban 1500 and Tahoe (2007–2008) depending on Active Brake Control presence.
• GMC Sierra 1500 and Yukon/Yukon XL fitment depends on trim and RPO JL4 code.

What are the key technical specifications I need to know?

This master cylinder is built from aluminum alloy and sized to match the original hydraulic properties so braking balance and pedal feel are preserved. Threading and outlet sizes follow common OEM standards for the listed models.

• Bore diameter: 1.25 inch, matching OEM hydraulic sizing.
• Rearward and secondary outlet thread: M12 x 1.0 for brake line compatibility.
• Material: 101 aluminum alloy for corrosion resistance and strength.
• Includes plastic reservoir and fluid-level sensor pre-installed.

How do I confirm part compatibility and install it safely?

Always verify part cross-reference numbers and vehicle-specific notes before ordering. Installation requires proper brake line reconnection, bleeding to remove air, and confirming sensor wiring for dashboard fluid warnings.

• Reference numbers: M630453, NM4194, 1741152, 15821794, 15844166 for cross-checking.
• Enter your vehicle details in the listing and read the "Special Note" before purchase.
• Professional installation or experienced DIY with correct tools is recommended.
• After installation, bleed the brake system and verify no leaks and correct pedal travel.

Who is this product for? Owners or technicians replacing a failing master cylinder on compatible 2007–2008 Cadillac, Chevrolet, or GMC trucks and SUVs who want a complete, ready-to-install assembly. It’s aimed at people who prefer a single, pre-assembled unit that includes the reservoir and sensor to cut installation time and reduce parts mismatch risk. If you need an exact-fit replacement backed by a one-year unlimited-mileage guarantee and you’ve confirmed fitment with the provided reference numbers, this A-Premium assembly is a practical choice. For uncertain fitment, review vehicle RPO codes or consult a mechanic before ordering.

Note: This listing covers specific model years and trims—verify your vehicle information and special notes on the product page to ensure correct fitment prior to purchase.