For DIY mechanics and professionals tackling brake system repairs, the ACDelco 18M870 Professional Durastop Brake Master Cylinder is a reliable, high-quality replacement part. Engineered to meet strict performance standards (SAE J1153 and J1154), this master cylinder is built from durable aluminum and iron castings, designed to handle the stress of modern braking systems without putting extra strain on your brake booster mounting.
It comes pre-assembled and ready to install right out of the box – no additional assembly needed, and it's already set up for easy bench bleeding. The internal components use a mix of EPDM and SBR rubber, which offers superior resistance to heat, corrosion, and leaks. Every unit is pressure-tested to ensure safe, confident braking performance. The precise geometrical tolerances mean the body and plastic reservoir fit together perfectly for a proper seal and function. Inside, the piston assembly and return spring work to prevent brake drag, which can lead to premature brake pad wear. Whether you're restoring an older vehicle or maintaining a daily driver, this ACDelco Professional master cylinder delivers the fit, form, and function you expect from a trusted brand in automotive parts.
