Overview – SLOTTED HEX NUT 3864439 Series
The Cummins SLOTTED HEX NUT 3864439 fits Cummins fastening positions as the slotted hexagon nut with a castellated pin; because multiple part numbers interchange, we list the related series so you can match what is on your machine.
Parts Characteristics
A slotted hexagon nut that, paired with a cotter pin, locks a shaft end so it cannot back off under rotation. It carries the lock that a plain nut cannot hold, so a true, pinned nut keeps the assembly from unthreading on its own.
Applicable Models & Applications
Used across Cummins fastening positions specifying this slotted hex nut (series). Match the thread, the width and the slot count against your old nut – slotted nuts differ in how they lock and pin.
Maintenance & Replacement
Inspect the slots for corrosion and the pin for presence at every service. A nut that has lost its cotter pin backs off, and the backing is what drops the shaft end.
Replace rather than reuse a galled nut. A nut whose threads have picked up cannot seat true and the pin will not line up.
Confirm torque and pin the slot on fit. A nut left unpinned is a nut waiting to unscrew under the first reversal of load.
Keep common slotted hex nuts for your model on the bench. They cost almost nothing, they lock an expensive shaft, and a component open on a nut is a machine waiting on a small part.
Price Reference (USD)
The SLOTTED HEX NUT 3864439 generally falls in the USD 2-25 bracket, with expedited freight quoted separately.
Value & Service
We supply brand-new Cummins slotted hexagon nuts with the thread and slot confirmed against your fastening, so the shaft stays locked.
The SLOTTED HEX NUT family includes C6221415420; we can cross-check which one matches your serial number.
Racer Machinery helps you standardize Cummins General Parts procurement; the SLOTTED HEX NUT 3864439 can be set up as a repeat order for predictable servicing.
