Product Description
The Cummins 3928405 OEM Valve Cover with Oil Fill is the factory-correct aluminum valve cover assembly designed for 1989–1998 12-Valve Cummins 4BT and 6BT 5.9L engines. This genuine Cummins component includes the integrated oil fill port and is engineered to seal the top of the cylinder head while providing clean, reliable crankcase ventilation and long-term durability. Unlike aftermarket covers, this OEM unit guarantees proper gasket sealing, correct oil fill alignment, and long service life under heavy-duty diesel operating conditions.
Ideal for restoration, maintenance, or engine refresh projects, the 3928405 valve cover restores a clean, OEM appearance and prevents leaks often caused by warped or cracked aftermarket or high-mileage covers.
Fitment
- 1989–1993 Dodge Ram 2500/3500 with 5.9L 12-Valve Cummins (6BT)
- 1994–1998 Dodge Ram 2500/3500 with 5.9L 12-Valve Cummins (6BT)
- Cummins 4BT 3.9L (industrial and automotive applications using 12V-style valve cover)
- Cummins 6BT 5.9L B-Series engines (1989–1998 12-Valve configuration)
Note: This is the single-piece OEM 12V valve cover with integrated oil fill — not the multi-piece ISB/24V style cover.
Cross-Reference (Cummins-Only)
Related Cummins top-end and sealing components:
• Cummins 3900267 Tappet Cover Bolt Grommet Seal
• Cummins 3904409 OEM Valve Stem Guide – 51.75mm
• Cummins 3903924 OEM Timing Pin – 12-Valve
FAQ
Is this the correct OEM valve cover for all 12-Valve 5.9L Cummins engines?
Yes — the 3928405 valve cover fits 1989–1998 12V Cummins 4BT and 6BT engines, including Ram 2500/3500 applications.
Does this valve cover include the oil fill cap?
This listing includes the valve cover with the oil fill opening. The oil fill cap may be sold separately depending on inventory.
Will this reduce oil leaks compared to old or aftermarket covers?
Yes. Warped or cracked aftermarket covers commonly leak. A genuine Cummins cover ensures proper sealing and correct geometry.
Does this fit the 24-Valve ISB engines?
No — this is strictly for 12-Valve Cummins engines. The 24V ISB uses a multi-piece valve cover system.
Can this be used on performance or modified engines?
Yes. This OEM valve cover is suitable for stock, towing, and mild performance builds requiring factory fitment and sealing.
Specifications for cummins 3928405
| Specification | Value |
|---|---|
| Brand | Cummins Genuine Parts |
| Part Number | 3928405 |
| Component Type | Valve Cover with Integrated Oil Fill |
| UPC | Not Published |
| GTIN | Not Published |
| Cross Reference | Used across 1989–1998 12V B-Series valve cover assemblies |
| E-Codes | N/A |
| Shipping Weight | Approx. 3.0 lbs |
| Package Dimensions | 24 x 6 x 6 in |
| Prop 65 Warning | Not Applicable |
