OTO-KAUTOPARTS Brake Master Cylinder for Chevy Silverado & GMC Sierra 2005-2007, Aluminum

OTO-KAUTOPARTS Brake Master Cylinder is a direct-fit replacement that restores hydraulic braking control for compatible 2005–2007 Chevy Silverado 1500 and GMC Sierra 1500 models.

This aluminum master cylinder assembly is manufactured to match OEM mounting points, outlet threads, and reservoir/sensor integration so you can replace a worn or leaking unit without modifying your pickup. It fits Silverado and Sierra crew cab and Classic models with the specified engines and vacuum brake systems, and it includes the reservoir and sensor for a near-complete swap-out. Before ordering, confirm the part number and vehicle RPO codes to ensure compatibility.

How do I know this master cylinder fits my Silverado or Sierra?

Check the vehicle fitment details and cross-reference part numbers before purchasing. This unit is listed for 2005–2006 Chevrolet Silverado 1500 and 2007 Silverado 1500 Classic (and equivalent GMC Sierra models) with specific RPO codes and vacuum brake systems.

• Compatible years: 2005–2006, plus 2007 Classic models
• Engines covered: 4.3L, 4.8L, 5.3L, 6.0L (V6 and V8 variants)
• Check vehicle RPO codes: JF3 or JF7 for some crew cab applications
• Cross-reference part numbers: M630325, 15183822, MC390930, MCA630325, MC142290, NMC22414

What are the key specifications and materials of this brake master cylinder?

The OTO-KAUTOPARTS master cylinder is cast from aluminum and engineered for standard hydraulic dimensions used on the listed trucks. It provides two outlet ports and accepts standard 1/2-20 fittings, matching many factory brake line connections.

• Material: durable aluminum construction
• Bore diameter: 1.125 inches
• Outlet thread sizes: rearward and secondary both 1/2-20
• Outlets: 2 (front and rear circuit ports)

What comes in the box and how simple is installation?

The package includes the master cylinder, the fluid reservoir, and the sensor, plus basic packaging for protection. The part is built for bolt-on replacement—no welding or drilling required—so DIY mechanics with basic tools can complete the swap in a single session, though bleeding the brake system is required afterward.

• Included: master cylinder, reservoir, sensor
• Mounting: direct-fit bolt pattern — no drilling/welding
• Installation: requires brake line fittings, common hand tools, and brake bleeding
• Condition: new unit, inspect on arrival for correct specs

What warranty and support does OTO-KAUTOPARTS provide?

OTO-KAUTOPARTS backs this master cylinder with a one-year warranty and offers customer support to address fitment questions or product concerns. If the part does not match the listed specifications on receipt, contact the seller for assistance.

• Warranty: one-year coverage from OTO-KAUTOPARTS
• Support: 24-hour online consultation and customer service
• Return/help: contact seller for incorrect fitment or defects

Who is this for: This master cylinder is intended for owners or technicians working on 2005–2007 Chevy Silverado 1500 or GMC Sierra 1500 trucks who need a reliable, direct-fit replacement for a failing or leaking brake master cylinder. It's well suited for DIY mechanics comfortable with brake-line work and bleeding, as well as professional shops looking for an aftermarket option that matches OEM mounting and thread specifications. Always verify your vehicle's part numbers and RPO codes before ordering to ensure proper fitment.