Product Description
Keep crankcase pressure under control on your 2003-2005 Dodge Ram 5.9L Cummins with the Cummins 3957987 OEM crankcase breather filter. This genuine Cummins CCV (crankcase ventilation) filter sits on top of the valve cover and separates oil mist from blow-by gases before they are routed back into the intake. If your truck is building crankcase pressure or leaving an oily film on the engine bay, this is the factory-correct replacement you want on your ISB 5.9L.
Because it’s an OEM Cummins 3957987 breather housing, you get the same internal media, molded housing, and sealing surfaces that your engine was designed around. The assembly includes the correct O-ring for a leak-free install, making this the easiest way to restore proper crankcase ventilation and protect turbo seals, front and rear main seals, and other sensitive gaskets from over-pressure.
- Genuine Cummins 3957987 CCV crankcase breather filter assembly
- Direct-fit for 2003-2005 Dodge Ram 2500/3500 with 5.9L ISB Cummins
- Mounts on top of factory valve cover – no fabrication required
- Includes new O-ring for a proper seal and clean install
- Helps control crankcase pressure and reduce oil leaks and seepage
- Restores OE performance and emissions function of CCV system
- Backed by Cummins quality and CPP Diesel’s knowledgeable support
Fitment
- 2003, 2004, 2005 Dodge Ram 2500 5.9L Cummins (ISB)
- 2003, 2004, 2005 Dodge Ram 3500 5.9L Cummins (ISB)
- Location: Crankcase breather / CCV filter housing on top of valve cover
- Engine family: ISB 5.9L 24V (common rail)
- Also used on select ISB/QSB/ISC/ISL industrial and medium-duty applications – always verify by engine serial number (ESN) before ordering for non-Ram uses.
Important: This 3957987 breather filter fits 2003–2005 applications only. 2006–2007 5.9L Cummins trucks use a different design that requires a complete valve cover assembly and will not accept this drop-in CCV filter.
Cross-Reference & Related Cummins Parts (CPP Diesel)
Pair this Cummins 3957987 breather filter with other genuine Cummins parts from CPP Diesel when you’re refreshing the top end of your 5.9L:
- CUMMINS 3944797 OEM CRANKCASE BREATHER WITH OIL FILL HOLE – 5.9L (1989–2002)
- CUMMINS 3969987 OEM INTAKE AIR HEATER GRID – 5.9L 24V (1998.5–2007)
- CUMMINS 3959574 OEM PISTON COOLING NOZZLE PLUG (DELETE) – ISB 5.9L / 6.7L
- CUMMINS 3945707 OEM FUEL DRAIN TUBE (VP44 RETURN LINE) – 5.9L 24V
Why Choose Genuine Cummins from CPP Diesel?
CPP Diesel only sells genuine Cummins 3957987 crankcase breather filters, never white-box or copycat imports. That means precise fitment, correct internal filtration media, and the durability you expect from Cummins. Combined with CPP Diesel’s fast shipping and diesel tech support, this makes maintaining your 5.9L Cummins simple and hassle-free.
FAQ
How often should I replace the Cummins 3957987 crankcase breather filter?
For most 2003-2005 5.9L Cummins trucks, the CCV filter is typically serviced around 67,500 miles or sooner if you notice excessive crankcase vapors, oil residue on the valve cover, or increased oil leaks. Always follow your maintenance schedule and inspect the breather during major services.
What symptoms indicate a clogged crankcase breather filter?
Common symptoms include oil film on the valve cover or intake components, elevated crankcase pressure, oil seepage at seals and gaskets, and occasional smoke or odor from blow-by gases. If you see these issues on a 2003–2005 ISB 5.9L, replacing the 3957987 CCV filter is a smart first step.
Does this Cummins 3957987 filter fit 2006–2007 5.9L Cummins trucks?
No. 2006–2007 5.9L Cummins engines use a different CCV system that integrates the filter into the valve cover. Those applications generally require a complete valve cover assembly and cannot use this 3957987 drop-in breather filter.
Is this a genuine Cummins part or an aftermarket replacement?
This is a genuine Cummins OEM 3957987 crankcase breather filter sourced through CPP Diesel. You get authentic Cummins quality, proper fitment, and the correct CCV separation media for long service life.
Can I install the 3957987 CCV filter myself?
Most experienced DIY owners can install this filter with basic hand tools. The breather housing is held to the valve cover with bolts; once removed, you clean the sealing surface, replace the assembly with the new O-ring, and torque fasteners to spec. Always follow Cummins or factory service procedures for your specific vehicle.
Specifications for cummins 3957987
| Brand | Cummins |
|---|---|
| Part Number | 3957987 |
| UPC | 193807301637 |
| GTIN | 193807301637 |
| Shipping Info | Ships as a small parcel item; approximate shipment weight 0.8 lb. Packaged in factory Cummins carton. |
| Cross Reference | Mopar 5093067AA; 3964093; 4935078; 4935079; PAI 050521OEM (verify by ESN before using as a substitute). |
| E-Codes | Not specified |
| Prop 65 | This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov. |
