Product Description
The CUMMINS 3947799 OEM FUEL RAIL PRESSURE RELIEF VALVE (PRV) is designed for 2003–2007 Dodge Ram trucks equipped with the 5.9L common rail Cummins diesel engine. This genuine Cummins pressure relief valve helps regulate maximum fuel rail pressure and protects critical fuel system components from excessive pressure conditions.
Use this part when diagnosing fuel pressure issues, excessive rail pressure, pressure bleed-off, trouble codes, or during fuel system repairs. Always verify fitment by part number and engine serial number before ordering.
FEATURES
- Genuine Cummins OEM fuel rail pressure relief valve
- Designed for common rail 5.9L Cummins fuel systems
- Direct-fit replacement for factory-installed PRV
- Helps maintain proper fuel rail pressure control
- Protects fuel system components from excessive pressure
- Ideal for maintenance, repair, or fuel system restoration
FITMENT
- 2003–2007 Dodge Ram 2500 5.9L Cummins Common Rail
- 2003–2007 Dodge Ram 3500 5.9L Cummins Common Rail
- 5.9L ISB Cummins equipped with Bosch common rail fuel systems
WHAT'S INCLUDED
- 1 Cummins 3947799 OEM Fuel Rail Pressure Relief Valve (PRV)
CROSS-REFERENCE AND RELATED PRODUCTS
- Cummins 3947799
- Common Rail Fuel Rail Assemblies
- Bosch CP3 Injection Pump Components
- Fuel Rail Pressure Sensors
SPECIFICATIONS
- Manufacturer: Cummins
- Part Number: 3947799
- Part Type: Fuel Rail Pressure Relief Valve (PRV)
- Fuel System Type: Common Rail
- Engine Compatibility: 5.9L Cummins
- Fitment Years: 2003–2007
- Vehicle Application: Dodge Ram 2500 / 3500
- Condition: New OEM Cummins
- Installation Type: Direct Replacement
- Fuel System Component: Yes
FAQ
Will this part fit my truck?
This valve fits many 2003–2007 Dodge Ram 2500 and 3500 trucks equipped with the 5.9L common rail Cummins engine. Always verify fitment using your engine serial number and part number before ordering.
What does a fuel rail pressure relief valve do?
The pressure relief valve protects the common rail fuel system by releasing fuel if pressure exceeds the designed operating limit.
What are the symptoms of a failing PRV?
Common symptoms include low rail pressure, hard starting, loss of power, pressure-related diagnostic trouble codes, or excessive fuel pressure bleed-off.
Is this a genuine Cummins part?
Yes. Cummins 3947799 is a genuine OEM fuel rail pressure relief valve manufactured to Cummins specifications.
Can a leaking PRV cause low fuel rail pressure?
Yes. A worn or damaged PRV can allow pressure to escape from the rail, resulting in reduced fuel pressure and drivability issues.
Do I need any related parts?
Inspect the fuel rail, fuel pressure sensor, high-pressure fuel lines, CP3 injection pump, and related fuel system components during service and replace worn parts as necessary.
