Bosch 0445120254 is a new, genuine Bosch common-rail injector, Cummins part number 5263317, for Cummins QSB 5.9L engines. It replaces Cummins 5254682, 3968846 and 3968546 and the earlier Bosch numbers 0445120209 and 0445120046. Sold as one injector; the engine takes six.

This is not the Dodge Ram pickup injector. A 2003 to early 2004 Ram 2500 or 3500 with the 5.9L takes Bosch 0445120255, remanufactured number 0986435503. See our 2003-2004 Ram 5.9L injector 0986435503, Bosch Authorized Remanufactured by VFI. A 2004.5 to 2007 Ram takes Bosch 0445120238, remanufactured number 0986435505. See our 2004.5-2007 Ram 5.9L injector 0986435505, Bosch Authorized Remanufactured by VFI.

This is the injector we see on hard starting, a miss that will not clear with a fuel filter, black smoke under load, or a cylinder-specific fault. We flow-test injectors on our own bench in Woodland, so if you are not certain which holes are down we can tell you before you buy six.

Specifications

Fits / Applications

• Cummins QSB 5.9L common-rail engines, including the marine QSB 5.9L, that call for Cummins injector 5263317
• Also replaces Cummins 5254682, 3968846 and 3968546 and Bosch 0445120209 and 0445120046
• Not for Dodge Ram 2500 / 3500 pickups: the 2003 to early 2004 Ram 5.9L takes Bosch 0445120255 and the 2004.5 to 2007 Ram 5.9L takes Bosch 0445120238
• QSB 5.9L engines were also built with other injector numbers, so match the number on your old injector or send us the engine serial number (ESN)
• Common-rail engines only, not for VP44 or mechanical-pump 5.9L engines
• Six injectors per engine

Part Numbers & Cross Reference

Bosch 0445120254  ·  Cummins 5263317  ·  Cummins (suffix versions) 5263317PX, 5263317NX, 5263317RX  ·  Cummins (earlier) 5254682, 3968846, 3968546  ·  Bosch (earlier) 0445120209, 0445120046  ·  Bosch remanufactured 0986435575

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 before you order and we will help you confirm the exact match against your build. That check is free and takes a few minutes.

The Bosch remanufactured (exchange) number for this injector is 0986435575. We do not list that one online. Call 530-668-0818 to ask about a remanufactured unit.

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. Send us your engine serial, VIN or build date before you order and we will help you confirm fitment, so the right part arrives the first time.

Not sure the injectors are the problem? We flow-test and diagnose injector complaints in-house. See our injector testing service before you buy a full set.