DS4 Electronic Injection Pump - NEW

Brand new, DS4831-5521S ULSD upgraded injection pump.

The pumps in this listing are New Old Stock (NOS), meaning they have factory build dates in the past.  They've never been on a motor and have been freshly serviced, re-sealed and run on our test bench. 

These are no longer produced by Stanadyne so quantities are extremely limited and totally random.

Since these are new, that means they have NEW optic sensors. An added bonus since optic sensors were discontinued by Stanadyne at the end of 2024. They also have new fuel solenoid, stepper motor, fuel shut off, housing, head & rotor, etc.. Nothing is remanufactured.

All model numbers other than 5068 are compatible with a 5521 replacement.  If you have a 5068, you can run this pump with a tune update to match it.

NO CORE RETURN REQUIRED since this is a 100% new pump.  You can take advantage of our core buy program, separately, however.