This is the Alliant Power AP55133, a common-rail fuel injector remanufactured by Alliant Power. It is the remanufactured version of Bosch 0445120133, the injector Bosch catalogs for the Cummins QSC 8.3L from 2003 to 2013, and it replaces Cummins 3965749, 4945463 and 4993482. Sold as one injector; the engine takes six. A refundable core applies.

The 8.3L Cummins used more than one Bosch common-rail injector. The ISC 8.3L, and the Case IH and New Holland engines that use CNH number 87581565, take Alliant Power AP55532 or Bosch 0445120272 (Cummins 5263305), not this one. Hard starting, a rough idle, a miss under load, smoke, fuel in the oil or low rail pressure from high injector return flow are the usual reasons these get replaced. Rule out the fuel filters, the supply side and the connector tubes first, then match the number on your old injector before you order.

Specifications

Fits / Applications

• Cummins QSC 8.3L with Bosch common rail, 2003 to 2013 (the Bosch catalog listing for this injector)
• Engines that take Cummins injector 3965749, 4945463 or 4993482
• Not for engines that take Cummins 5263305 or CNH 87581565 (the ISC 8.3L and Case IH and New Holland injector). Those take Alliant Power AP55532 or Bosch 0445120272.
• Six injectors per engine

Change the fuel filters and keep everything clean when you fit injectors: dirt in the high-pressure side is the usual cause of an early repeat failure. Sellers of these injectors recommend new high-pressure connector tubes with new injectors on the 8.3L common rail, because a worn or dirty tube contaminates the new injector. At the least, pull the tubes and inspect them closely.

Part Numbers & Cross Reference

Cummins 4993482  ·  Cummins 4945463  ·  Cummins 3965749  ·  Cummins 4993482PX  ·  Bosch new version 0445120133  ·  Bosch (earlier number) 0445120038

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

Will the Alliant Power AP55133 fit my Cummins QSC 8.3?

It is the remanufactured version of Bosch 0445120133, which Bosch lists for the QSC 8.3L from 2003 to 2013. It fits if your engine takes Cummins 3965749, 4945463 or 4993482. Call 530-668-0818 with your engine serial number and we will confirm it.

What numbers does the AP55133 replace?

Cummins 3965749, 4945463, 4993482 and 4993482PX. It is the remanufactured version of Bosch 0445120133, which replaced Bosch 0445120038.

Is the AP55133 the same as the AP55532?

No. AP55532 is for the ISC 8.3L and replaces Cummins 5263305 and Case IH / New Holland 87581565. AP55133 replaces Cummins 4993482. The catalogs we checked do not cross one to the other, so go by the number on your old injector.

Is the AP55133 new or remanufactured, and is there a core?

It is remanufactured by Alliant Power. A refundable core charge applies, and it is refunded when we receive your rebuildable old injector. The new version of the same injector is Bosch 0445120133.

Related Parts

• Cummins QSC 8.3L Common-Rail Fuel Injector | Bosch 0445120133 New (Cummins 4945463, 4993482)
• Cummins ISC 8.3L, Case IH & New Holland Common-Rail Fuel Injector | Bosch 0445120272 New
• Cummins ISC 8.3L, Case IH & New Holland Common-Rail Fuel Injector | Alliant Power AP55532 Remanufactured
• Cummins ISC & ISL 8.9L HE300VG Turbo Actuator Kit | Holset 6382091HX Remanufactured
• Common Rail Diesel Injector Testing & Rebuild Service

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.