Product Description
CUMMINS 3973511 OEM ENGINE OIL FILL CAP – RAM 5.9L/6.7L (1998.5–2024)
The genuine CUMMINS 3973511 OEM engine oil fill cap is the factory-correct replacement for a wide range of 1998.5–2024 5.9L and 6.7L Cummins engines. If your original cap is cracked, missing, or no longer sealing properly, this OE unit restores the correct pressure retention needed to keep contaminants out and prevent oil spray or seepage during operation. Designed and tested by Cummins, this cap ensures reliable fit, long-term durability, and proper engagement with the valve cover.
This cap installs in seconds and provides the exact OE fitment required for ISB engines across multiple generations of Ram trucks. Combine it with genuine Cummins seals, gaskets, and service components for a complete OEM-level maintenance approach.
Fitment Details
- Engine: 5.9L Cummins ISB (1998.5–2007), 6.7L Cummins ISB (2007.5–2024)
- Applications: Dodge/Ram 2500 & 3500 (1998.5–2024), plus various industrial & commercial ISB platforms
- Position: Valve Cover – Engine Oil Fill Opening
Always verify by VIN/ESN, especially on commercial and industrial Cummins ISB variants.
Cross-Reference & Companion Cummins Parts
- CUMMINS 3945917 OEM VALVE COVER GASKET – 5.9L
- CUMMINS 4988747 OEM VALVE COVER GASKET – 6.7L
- CUMMINS 3957890 OEM CRANKCASE BREATHER ELEMENT
- VIEW ALL GENUINE CUMMINS PARTS
Cross-reference identifiers (verify by application): 3973511, 3915705 (earlier variant), 3949888 (assembly supersession reference).
Specifications for cummins 3973511
| Attribute | Value |
|---|---|
| Brand | Cummins (Genuine OEM) |
| Part Number | 3973511 |
| Function | Engine oil fill cap for Cummins ISB engines |
| Engine Compatibility | 5.9L ISB (1998.5–2007), 6.7L ISB (2007.5–2024) |
| UPC | 193464031314 |
| GTIN | 193464031314 |
| Cross Reference | 3915705, 3949888 (verify supersession by ESN) |
| E-Codes | Used across multiple EPA-certified ISB platforms (verify specific calibration) |
| Prop 65 Warning | WARNING: This product may contain materials known to the State of California to cause cancer or reproductive harm. Visit https://www.P65Warnings.ca.gov for more information. |
| Shipping Weight | 0.25 lb (approx.) |
| Shipping Method | Standard ground; expedited options available at checkout |
Frequently Asked Questions
WILL THIS FIT BOTH 5.9L AND 6.7L CUMMINS ENGINES?
Yes. CUMMINS 3973511 is used across ISB platforms from 1998.5–2024, including both the 5.9L and 6.7L engines. Always confirm by VIN/ESN for industrial or medium-duty applications.
IS THIS A COMPLETE ASSEMBLY OR JUST THE CAP?
This is the complete OE engine oil fill cap assembly as supplied by Cummins.
WHAT IF MY ORIGINAL CAP WILL NOT TIGHTEN?
A worn fill cap is common on higher-mileage engines. Replacing it with the genuine Cummins 3973511 restores proper sealing and prevents crankcase vapor or oil mist leaks.
CAN THIS FIX BLOW-BY OR OIL CONSUMPTION?
No. It only seals the fill opening. Excessive crankcase pressure should be diagnosed through the crankcase breather system and overall engine condition.
IS THIS BETTER THAN AFTERMARKET CAPS?
Yes. Genuine Cummins caps guarantee proper sealing tension, heat resistance, and long-term fitment accuracy. Aftermarket copies often become loose or brittle over time.
