MPA Electrical NM1581 Brake Master Cylinder

Brake Master Cylinder for Front Disc Brake Trucks

MPA Electrical NM1581 is a new brake master cylinder for select Chevrolet and GMC trucks and vans with front disc brakes. It is built as a standard replacement with an integral reservoir, cast iron body, and a 1-inch bore to help restore firm hydraulic braking response.

The MPA Electrical New with front disc brakes line focuses on direct-fit brake hydraulic replacements that are tested against OE specifications. NM1581 follows that approach for drivers servicing a Chevrolet C10, Chevrolet G10, GMC C1500, GMC G1500, GMC G15, GMC G15/G1500 Van, or GMC Jimmy with the correct front disc brake setup.

• Standard replacement brake master cylinder
• 1-inch master cylinder bore diameter
• Cast iron master cylinder construction
• Integral reservoir design with reservoir included
• Push rod included
• Master cylinder cap included
• DOT 3 fluid type
• Two mounting holes with 0.415-inch mounting hole diameter
• New condition

Detailed Product Overview

MPA Electrical NM1581 is engineered for brake hydraulic service on 1973-1980 Chevrolet and GMC applications with front disc brakes. It is a direct replacement brake master cylinder that uses an integral reservoir layout and a cast iron housing to match the needs of classic truck and van brake systems. This part number, NM1581, is also cross-referenced to 6260961 and 14004846 for the same application.

Compatible With 1975-1980 Chevrolet C10, front disc brakes; 1975-1980 Chevrolet G10, front disc brakes; 1979-1980 GMC C1500, front disc brakes; 1979-1980 GMC G1500, front disc brakes; 1975-1978 GMC G15, front disc brakes; 1974 GMC G15/G1500 Van, front disc brakes; and 1973-1974 GMC Jimmy, front disc brakes. NM1581 is a practical choice when servicing a Chevrolet C10 or GMC Jimmy brake system that requires the correct master cylinder bore and reservoir configuration.

Common Brake Issues This Part Can Address

• Low or inconsistent brake pedal feel caused by master cylinder wear
• Internal hydraulic leakage that reduces braking performance
• Brake fluid loss at the master cylinder body or seals
• Pedal travel problems related to an incorrect bore or worn cylinder
• Restoration work on older Chevrolet and GMC front disc brake systems

Installation Notes and Tips

Verify the vehicle’s front disc brake configuration before ordering, since this part is listed for specific Chevrolet and GMC applications only. Confirm the mounting pattern, bore size, and push rod setup against the original unit before installation. Bench bleeding the master cylinder before final assembly helps reduce trapped air in the hydraulic system and supports proper pedal feel after service.

Quality Assurance

MPA Electrical states that its brake master cylinders are checked against OE specifications using sample-based engineering data and controlled test procedures. That process is used to help ensure consistent braking performance out of the box for the NM1581 brake master cylinder.