This is the Alliant Power AP55117, an XPI common-rail fuel injector for the Cummins ISX12, remanufactured by Alliant Power. It replaces Cummins 2872544 and 2872289, including the Cummins exchange numbers 2872544PX, 2872544RX, 2872544NX and 2872289NX. Interstate-McBee sells its version of the same injector as R-2872544. A refundable core applies. The engine takes six, and this listing is for one injector.

The ISX12 did not use one XPI injector for its whole run. AP55117 covers the engines that call for Cummins 2872544 or 2872289. Its sister, AP55103, replaces Cummins 2897518, the injector catalogs list for EPA13 ISX12 engines. The two are different injectors and no catalog crosses one to the other, so do not order by engine name alone. Catalogs also list Cummins 2872544 for the QSX industrial version of this engine. The usual reasons to replace an XPI injector are hard starting, a rough idle, a miss, smoke, low power or an injector fault code. Dirty fuel is what wears them, so fit new fuel filters at the same time.

Specifications

Fits / Applications

• Cummins ISX12 with the XPI common-rail fuel system, on engines that call for injector 2872544 or 2872289
• Replaces Cummins 2872544, 2872544PX, 2872544RX, 2872544NX, 2872289 and 2872289NX
• Catalogs also list Cummins 2872544 for the QSX industrial version of this engine. Confirm an off-highway engine by CPL before you order.
• Not for ISX12 engines that call for Cummins 2897518, the injector listed for EPA13. Those take Alliant Power AP55103.
• Not for the ISX15. The 15 liter engine uses its own XPI injectors.
• Six injectors per engine. This listing is for one injector.

Alliant Power’s install bulletin for its Cummins ISX injectors gives the steps: clean the injector bore, oil the injector O-ring with clean engine oil, fit a new injector feed tube, then tighten the hold-down bolt and the feed tube nut in stages to the Cummins specification. Keep the injector harness clear of the rocker levers and the engine brake housing. The same bulletin says each Alliant Power ISX injector carries its own trim code, which is entered with a scan tool, so check the label on the injector. Change the fuel filters at the same time, because dirty fuel is the main thing that wears XPI injectors.

Part Numbers & Cross Reference

Alliant Power AP55117  ·  Cummins 2872544  ·  Cummins 2872544PX  ·  Cummins 2872544RX  ·  Cummins 2872544NX  ·  Cummins 2872289  ·  Cummins 2872289NX  ·  Interstate-McBee R-2872544  ·  D&W Diesel 148-075-0009

Cross-reference numbers can change with engine serial, build year and emissions tier, so treat this list as a starting point. Send us your engine serial number and we will confirm the exact match against your build before anything ships. That check is free and takes a few minutes.

Frequently Asked Questions

What Cummins numbers does the AP55117 replace?

Cummins 2872544 and 2872289, including the exchange numbers 2872544PX, 2872544RX, 2872544NX and 2872289NX. The Interstate-McBee number for the same injector is R-2872544.

What is the difference between AP55117 and AP55103?

Both are Alliant Power remanufactured XPI injectors for the Cummins ISX12, but they replace different Cummins injectors. AP55117 replaces 2872544 and 2872289. AP55103 replaces 2897518, which catalogs list for EPA13 engines. Order by the number on your old injector.

Is the AP55117 new or remanufactured, and is there a core?

It is remanufactured by Alliant Power. A refundable core applies, and it comes back when we receive your old injector in rebuildable condition.

How do I make sure this is the right injector for my ISX12?

Read the Cummins number on your old injector and the CPL on the engine dataplate, then call 530-668-0818 with those and the engine serial number. We will match it before you order.

Related Parts

• Cummins ISX15 EPA10 XPI Common-Rail Fuel Injector | Alliant Power AP55101 Remanufactured
• Cummins X15 & ISX15 EPA17 to EPA24 XPI Common-Rail Fuel Injector | Alliant Power AP55128 Remanufactured
• Cummins ISX12 XPI Fuel Injector | Alliant Power AP55103 Remanufactured
• Cummins ISX15 EPA07 HE500VG Turbocharger with Actuator | Alliant Power AP90960 Remanufactured (OE 4309076)

Why Buy From Valley Fuel Injection

We are a diesel fuel-injection and turbocharger shop in Woodland, CA, rebuilding pumps, injectors and turbos on our own benches since 1993, not a drop-ship storefront. When you call, you talk to the people who test these units. We verify fitment against your engine serial, VIN or build date before anything ships, so the right part arrives the first time.

Not sure the injectors are the problem? We test and diagnose in-house before you buy. See our common rail injector testing and rebuild service.