The Dorman - First Stop Brake Master Cylinder M630920 converts brake-pedal force into the hydraulic pressure that operates your brake circuits, and it drops in as a direct-fit replacement for the 2013 Infiniti JX35, 2014-2017 Infiniti QX60, and 2013-2018 Nissan Pathfinder [All engines]. Dorman engineers it to reproduce the original master cylinder's design and function on these applications, using all-new materials for a safe, durable replacement.
- Cast iron housing: the cylinder housing is built to match the casting material of the original part for similar performance.
- EPDM rubber components: made from a high-quality EPDM compound for resistance to glycol-based brake fluid.
- 100% new: made entirely of new materials, not remanufactured.
- SAE standards: made to meet rigorous SAE International standards.
It has a 1.0625 in bore and two outlets with M12 x 1.0 threads, and is set up for a single reservoir. The reservoir, fluid-level sensor, and mounting hardware are not included — transfer the originals or source them as directed by the vehicle service procedure. Country of origin: China.
Interchange: 100-3951 · 1003951 · 11-4632 · 114632 · 130.42421 · 355-67078 · 35567078 · NM55635 · 460103JA0A · MC391482. Manufacturer part number M630920.
This part cross-references / interchanges with the following part numbers:
Frequently Asked Questions
What vehicles does this master cylinder fit?
It's a direct-fit replacement for the 2013 Infiniti JX35, 2014-2017 Infiniti QX60, and 2013-2018 Nissan Pathfinder (all engines). Check the Buyer's Guide tab to confirm your vehicle.
Is a reservoir included?
No. The reservoir, fluid-level sensor, and mounting hardware are not included; transfer the originals or source them as directed by the vehicle service procedure.
What is the bore size and outlet thread?
The bore diameter is 1.0625 in, and it has two outlets using M12 x 1.0 threads.
Is this new or remanufactured?
It is 100% new, made entirely of new materials and not remanufactured, and is made to meet rigorous SAE International standards.
What are signs my master cylinder may need replacing?
A sinking or spongy brake pedal, a pedal that slowly drops under steady pressure, or fluid loss with no visible line leak. Diagnose the cause before replacing.