Product Description
CUMMINS 4938189 OEM EXPANSION PLUG (FREEZE / CORE PLUG) – RAM 5.9L/6.7L (2003–2018)
The genuine CUMMINS 4938189 OEM expansion plug is the factory steel freeze plug used to seal critical coolant passages in the engine block of 2003–2018 5.9L and 6.7L Cummins engines. Whether you're rebuilding a long block, repairing a coolant leak, or replacing aged plugs due to corrosion, this OEM core plug ensures the proper fit, sealing surface, and durability required for long-term engine reliability.
Low-quality aftermarket freeze plugs often deform during installation, leak under pressure, or corrode prematurely. With a real Cummins expansion plug, you get the correct metallurgy, heat resistance, and engineered press-fit required for B-series and ISB engines. If you're refreshing your cooling system or assembling a motor, this is the exact plug Cummins specifies.
Key Features
- Genuine Cummins OEM freeze/core plug – precise fit and factory materials.
- Seals engine block coolant ports on 5.9L & 6.7L Cummins ISB engines.
- Corrosion-resistant steel construction for long-term reliability.
- Perfect for rebuilds, coolant leak repairs, and preventative maintenance.
- Engineered press-fit ensures retention through heat cycles and vibration.
Fitment Details
- Engines: 5.9L Cummins ISB, 6.7L Cummins ISB
- Years: 2003–2018 (verify by VIN/ESN for exact plug quantity and placement)
- Applications: Dodge/Ram 2500 & 3500 — all ISB-equipped models
- Typical Use: Block coolant passage freeze/core plug replacement
Cross-Reference & Companion Cummins Parts
Pair CUMMINS 4938189 with other commonly replaced Cummins components during cooling system or long-block service:
- CUMMINS 3966659 OEM WATER PUMP – 5.9L / 6.7L
- CUMMINS 3967921 OEM THERMOSTAT KIT
- CUMMINS 3922072 FRONT COVER GASKET
- VIEW ALL GENUINE CUMMINS OEM PARTS
Common cross-reference numbers: 4938189, 3930323 (verify by VIN/ESN).
Installation Notes
- Clean the block bore thoroughly before installing the new plug.
- Apply a thin layer of appropriate sealant if required by Cummins documentation.
- Use a flat driver or correct mandrel to press the plug evenly into place.
- Inspect all expansion plugs during rebuilds—replace any that show corrosion or seepage.
Specifications for cummins 4938189
| Attribute | Value |
|---|---|
| Brand | Cummins (Genuine OEM) |
| Cummins Part Number | 4938189 |
| Alternate Part Numbers | 3930323 (verify by VIN/ESN) |
| Function | Engine block expansion / freeze / core plug |
| Engine Compatibility | 5.9L ISB (2003–2007), 6.7L ISB (2007.5–2018) |
| Vehicle Fitment | Dodge/Ram 2500 & 3500 (5.9L & 6.7L Cummins) |
| UPC | 190910208101 |
| GTIN | 190910208101 |
| Shipping Weight | Approx. 0.05 lb |
| Shipping Method | Standard ground shipping; expedited available |
| E-Codes / Emissions | Non-emissions component; coolant system sealing |
| 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 production batch) |
Frequently Asked Questions
DOES THIS FIT BOTH 5.9L AND 6.7L CUMMINS ENGINES?
Yes. CUMMINS 4938189 is used on a wide range of 2003–2018 5.9L and 6.7L ISB engines. Always verify by VIN/ESN for exact plug quantity and locations.
HOW MANY EXPANSION PLUGS DOES MY ENGINE NEED?
Quantities vary by engine casting, year, and model. Inspect your block carefully or refer to Cummins service documentation for exact placement.
SHOULD I REPLACE ALL FREEZE PLUGS DURING A REBUILD?
Yes—it is strongly recommended. Freeze plugs are inexpensive insurance against future coolant leaks and corrosion failures.
IS THIS A GENUINE CUMMINS FREEZE PLUG?
Yes. CPP Diesel only supplies authentic Cummins OEM components for proper fit and long-lasting reliability.
CAN A LEAKING FREEZE PLUG CAUSE OVERHEATING?
Absolutely. Loss of coolant from a failed freeze plug can lead to overheating and severe engine damage if not addressed quickly.
