MPA Electrical B3040 Power Brake Booster

Remanufactured Vacuum Brake Booster for Infiniti and Nissan

MPA Electrical B3040 is a remanufactured vacuum power brake booster built for direct replacement in select Infiniti QX4 and Nissan Pathfinder applications. It is engineered to deliver strong braking assist with reduced pedal effort, helping restore consistent brake feel in everyday driving.

Designed for 1998-2000 Infiniti QX4 and 1999-2000 Nissan Pathfinder models, this MPA Electrical brake booster uses a vacuum booster design with a metal housing and standard replacement service grade. The B3040 is supplied without the master cylinder, brake pedal rod extension, gasket or seal, front seal, or mounting bracket.

Key Features

• Remanufactured vacuum power brake booster
• Standard replacement brake service grade
• Metal housing construction
• 246.63 mm / 9.71 in diaphragm diameter
• 8 x 1.25 mm master cylinder stud thread size
• 2 mounting studs
• Master cylinder not included
• Brake pedal rod extension not included

Product Line Details

MPA Electrical reman vacuum brake boosters are built for drivers who need dependable brake assist restoration without replacing the entire brake system. The B3040 follows the brand line’s focus on vacuum seal integrity, pressure transfer, and end-of-line testing to verify function before release.

Detailed Description

This power brake booster is intended for vehicles that need restored vacuum-assisted braking performance. By increasing assist at the pedal, the booster helps the brake system respond with less driver effort. The B3040 is a fitment-based replacement for 1998-2000 Infiniti QX4 and 1999-2000 Nissan Pathfinder models, making it a practical choice when replacing a worn or leaking booster on those platforms. This part number is B3040.

This part cross-references 472101W700 for the same application.

What It Helps Fix

• Hard brake pedal feel
• Reduced vacuum assist
• Brake booster vacuum leakage
• Inconsistent pedal response
• Loss of braking assist on Infiniti QX4 and Nissan Pathfinder vehicles

Installation Notes

Verify master cylinder compatibility before installation, since the master cylinder is not included. Confirm the 8 x 1.25 mm stud thread size and 2-stud mounting layout match the original brake system. Inspect vacuum supply, pedal linkage, and sealing surfaces during replacement to help ensure proper brake assist after installation. This part number is B3040.

Quality Assurance

Each unit is end-of-line tested with proprietary equipment to confirm brake booster function and pressure transfer performance before it leaves the remanufacturing process.

Compatible Vehicles

• Fits 1998-2000 Infiniti QX4, N/A
• Fits 1999-2000 Nissan Pathfinder, N/A