Product Description
CUMMINS 3934047 OEM PISTON WRIST PIN – 5.9L ISB (2004.5–2007)
The genuine CUMMINS 3934047 OEM piston wrist pin is the exact hardened steel connecting pin used in 2004.5–2007 5.9L ISB common rail engines. This critical component supports the rotational connection between the piston and connecting rod, maintaining correct piston stability, alignment, and lubrication under extreme combustion pressure. If you are rebuilding your 5.9L ISB, replacing a damaged piston, or refreshing a high-mileage short block, OEM wrist pins are the only choice for strength, longevity, and precision fitment.
This Cummins wrist pin is machined and heat-treated to exact tolerances to prevent piston rock, skirt wear, and rod bushing distortion. Many failures seen in high-mileage engines—such as piston noise, misalignment, and excessive blow-by—are often tied to worn or aftermarket wrist pins. Using a real Cummins 3934047 pin ensures OE material hardness and dimensional accuracy for a stable, properly balanced rotating assembly.
Key Features
- Genuine Cummins OEM wrist pin – engineered for exact fit, hardness, and surface finish.
- Heat-treated steel construction designed for high-pressure common-rail combustion loads.
- Direct replacement for 2004.5–2007 5.9L ISB engines.
- Prevents piston rock, noise, and premature wear when used with OE pistons and rod bushings.
- Ideal for stock rebuilds, fleet engines, and performance-restored ISB applications.
Fitment Details
- Engine: 5.9L Cummins ISB Common Rail
- Years: 2004.5–2007
- Applications: Dodge Ram 2500 / 3500 with 5.9L common rail
- Notes: Always measure rod pin bushing clearance during rebuild; replace worn bushings when installing a new wrist pin.
Cross-Reference & Companion Cummins Parts
CPP Diesel stocks all major Cummins components used alongside the 3934047 wrist pin. Compatible OEM parts include:
- CUMMINS 3957649 PISTON RING SET – required when servicing pistons.
- CUMMINS 3942581 CONNECTING ROD BUSHING – replace during wrist pin installation for proper fitment.
- CUMMINS 3943478 OEM PISTON ASSEMBLY – OE piston designed to pair with this wrist pin.
- VIEW ALL GENUINE CUMMINS PARTS
Common Cummins cross-reference numbers: 3934047, 3934047NX, 3934047PX (verify per VIN/ESN).
Installation Notes
- Measure connecting rod pin bore before installation.
- Heat piston as required for thermal-fit installation (per Cummins procedures).
- Use new rod bushings for correct oil clearance and geometry.
- Lubricate surfaces during assembly to prevent galling on start-up.
Specifications for cummins 3934047
| Attribute | Value |
|---|---|
| Brand | Cummins (Genuine OEM) |
| Cummins Part Number | 3934047 |
| Alternate Numbers | 3934047NX, 3934047PX (verify with VIN) |
| Function | Piston wrist pin / connecting pin |
| Engine Compatibility | 5.9L ISB Common Rail (2004.5–2007) |
| Vehicle Fitment | Dodge Ram 2500/3500 5.9L |
| UPC | 193631147403 |
| GTIN | 193631147403 |
| Shipping Weight | Approx. 0.6 lb |
| Shipping Method | Standard ground; expedited available |
| E-Codes / Emissions | Not emissions-related |
| Prop 65 Warning | WARNING: May expose you to chemicals known to the State of California to cause cancer and reproductive harm. See www.P65Warnings.ca.gov. |
| Country of Origin | As labeled by Cummins (varies by batch) |
Frequently Asked Questions
IS THIS THE CORRECT WRIST PIN FOR MY 2004.5–2007 5.9L?
Yes. CUMMINS 3934047 is used in the common-rail 5.9L ISB piston assemblies from 2004.5–2007. Always verify with your VIN/ESN.
SHOULD I REPLACE THE CONNECTING ROD BUSHINGS?
Yes. We strongly recommend installing new bushings such as CUMMINS 3942581 to ensure correct oil clearance.
WILL THIS WORK WITH OEM PISTONS?
Yes—this is the factory wrist pin used with Cummins OEM pistons such as CUMMINS 3943478.
IS THIS PIN HARDENED LIKE THE ORIGINAL?
Yes. This genuine OEM pin is fully heat-treated to Cummins specifications for high-pressure ISB operation.
CAN AFTERMARKET WRIST PINS CAUSE ENGINE NOISE?
Yes. Incorrect hardness or diameter variance from non-OEM pins can cause piston rock, knocking, or premature skirt wear. OEM is recommended for rebuilds.
