MPA Electrical NM4073 Brake Master Cylinder

Brake Master Cylinder for GM Trucks and SUVs

The MPA Electrical NM4073 brake master cylinder is a standard replacement hydraulic component for select 2003-2005 Chevrolet Silverado 1500 and GMC Sierra 1500 models, plus 2003 Cadillac Escalade, Escalade ESV, Chevrolet Avalanche 1500, Suburban 1500, Tahoe, GMC Yukon, and Yukon XL 1500 with front disc brakes. It is built with an aluminum body, a 1.25-inch bore, and an integrated reservoir and cap for a direct service replacement.

MPA Electrical’s New with front disc brakes product line focuses on replacement brake hydraulics that are tested against OE specifications using controlled validation processes. This NM4073 master cylinder is intended for drivers replacing a worn or leaking unit on GM full-size trucks and SUVs that use DOT 3 brake fluid.

• Part number: NM4073
• Aluminum master cylinder construction
• 1.25-inch bore diameter
• Reservoir included; master cylinder cap included
• Standard replacement grade
• Uses DOT 3 brake fluid
• Two mounting holes with 0.42-inch mounting hole diameter
• Fits front disc brake applications listed below

Detailed Application Coverage

Compatible With 2003-2005 Chevrolet Silverado 1500, front disc brakes; 2003-2005 GMC Sierra 1500, front disc brakes; and 2003 Cadillac Escalade, Escalade ESV, Chevrolet Avalanche 1500, Suburban 1500, Tahoe, GMC Yukon, and Yukon XL 1500, all with front disc brakes. The NM4073 is a direct hydraulic replacement for vehicles that need restored pedal response and consistent brake pressure at the master cylinder.

This part cross-references OE numbers 18047527 and 19209239 for the same application.

What This Part Helps Address

• Low or inconsistent brake pedal feel
• External or internal master cylinder fluid leakage
• Brake warning symptoms caused by hydraulic wear
• Reduced braking performance from a failing master cylinder bore or seals
• Service replacement needs on GM trucks and SUVs with front disc brakes

Installation Notes

Before installation, verify the vehicle uses front disc brakes and confirm the mounting pattern, bore size, and brake fluid specification. This master cylinder does not include mounting hardware, gasket or seal, push rod, brake booster, sensor, or brake pressure switch. Bench bleeding is recommended before final installation, and the brake system should be filled with DOT 3 fluid only.

Quality Assurance

MPA Electrical tests each brake master cylinder against OE specifications using proprietary procedures and strict inspection protocols to help ensure consistent braking performance out of the box. The NM4073 is a new replacement part built for dependable hydraulic restoration on supported Chevrolet, GMC, and Cadillac applications.