MPA Electrical NM55493 Brake Master Cylinder

Brake Master Cylinder for Kia and Hyundai

Restore consistent brake pedal response with this MPA Electrical brake master cylinder, part number NM55493. It is a standard replacement for vehicles with front disc brakes and is built with an aluminum master cylinder body, plastic reservoir, and included cap for a direct hydraulic service replacement.

Key Features

• Brake master cylinder for brake hydraulic repair
• Aluminum master cylinder construction with plastic reservoir
• 0.877 bore diameter for OE-style hydraulic performance
• Compatible with DOT 3 or DOT 4 brake fluid
• Two mounting holes with 0.339 mounting hole diameter
• Reservoir and cap included; brake booster, push rod, and mounting hardware not included
• Standard replacement grade for everyday service use

Fitment Details

Fits 2011-2015 Kia Optima, N/A, new with front disc brakes. Fits 2011-2014 Hyundai Sonata, N/A, new with front disc brakes. This part cross-references OE numbers 585102T200 and 585103Q300 for the same application.

MPA Electrical NM55493 is engineered using OE sample data and tested against OE specifications to help deliver consistent braking performance right out of the box. It is a direct-fit brake master cylinder for Kia Optima and Hyundai Sonata models listed above, making it a practical choice when replacing a worn or leaking hydraulic unit. The NM55493 part number is also useful when verifying the correct master cylinder for front disc brake applications that use DOT 3 or DOT 4 fluid.

Common Problems This Part Can Address

• Low or inconsistent brake pedal feel
• External brake fluid leakage at the master cylinder
• Internal hydraulic bypass causing pedal drop
• Brake warning concerns related to master cylinder wear
• Reduced braking response from a failing hydraulic seal assembly

Installation Notes and Tips

Confirm reservoir, bore size, and mounting-hole layout before installation. Bench bleeding is recommended before connecting brake lines to reduce trapped air in the hydraulic system. Use clean DOT 3 or DOT 4 brake fluid only, and inspect the brake booster, lines, and fittings for wear or contamination during service. Mounting hardware, gasket or seal, push rod, and brake booster are not included.

Quality Assurance

MPA Electrical tests each unit against OE specifications using controlled processes and an OE sample library to support consistent fit and function. This NM55493 master cylinder is a new standard replacement part built for brake system restoration on the listed Kia and Hyundai applications.