Product Description
The CUMMINS 3904217 OEM MAIN BEARING CAP BOLT is a genuine Cummins 14mm hex head cap screw designed for 1989-1997 Dodge Ram 5.9L Cummins 12-valve diesel engines. This OEM fastener secures the main bearing caps to the engine block and is critical for maintaining proper crankshaft support, bearing alignment, and bottom-end durability.
Main bearing cap bolts experience extreme stress from engine load, RPM, towing, and cylinder pressure. Replacing worn, stretched, corroded, or damaged main cap bolts during engine service or rebuilds helps maintain proper clamping force and long-term engine reliability.
Manufactured to genuine Cummins OEM specifications, the 3904217 main cap bolt provides the proper fitment, thread engagement, and strength required for factory engine rebuilding standards.
FEATURES
- Genuine Cummins OEM main bearing cap bolt
- 14mm hex head cap screw design
- Fits 1989-1997 5.9L Cummins 12V engines
- Maintains proper main cap clamping force
- Designed for OEM engine rebuilding standards
- Direct-fit replacement hardware
- Helps maintain crankshaft stability and bearing alignment
- Ideal for engine rebuilds, repairs, and maintenance
FITMENT
- 1989-1993 Dodge Ram D250/D350/W250/W350 5.9L Cummins 12V
- 1994-1997 Dodge Ram 2500/3500 5.9L Cummins 12V
- Fits 14mm main cap applications
Fitment Note: Verify engine serial number and main hardware configuration before ordering.
WHAT'S INCLUDED
- 1 Cummins 3904217 OEM main bearing cap bolt
CROSS-REFERENCE & RELATED PRODUCTS
- ARP 247-5402 MAIN STUD KIT 14MM
- CUMMINS 3900630 OEM MAIN BEARING SET
- CUMMINS 3901090 OEM THRUST BEARING
- CUMMINS 3927772 OEM MAIN CAP DOWEL PIN
- CUMMINS OEM ENGINE HARD PARTS
WHY REPLACE MAIN CAP BOLTS?
Main cap hardware is critical to bottom-end engine stability. Over time, repeated torque cycles, engine stress, and rebuild procedures can weaken or stretch factory bolts. Replacing damaged or fatigued fasteners helps maintain proper crankshaft support and bearing alignment in demanding diesel applications.
SPECIFICATIONS
| Specification | Details |
|---|---|
| Manufacturer | Cummins |
| Part Number | 3904217 |
| Hardware Type | Main bearing cap bolt / hex head cap screw |
| Thread Size | 14mm |
| Engine Compatibility | 5.9L Cummins 12V |
| Fitment Years | 1989-1997 |
| Configuration | OEM replacement fastener |
| Condition | New Genuine Cummins OEM Part |
| Prop 65 | Warning: Cancer and Reproductive Harm — www.P65Warnings.ca.gov. |
FAQ
What does the Cummins 3904217 bolt secure?
This bolt secures the main bearing caps to the engine block and helps maintain crankshaft support and bottom-end stability.
Will this fit all 5.9L Cummins engines?
Cummins 3904217 is designed for 1989-1997 5.9L Cummins 12-valve applications using 14mm main hardware.
Should main cap bolts be replaced during an engine rebuild?
Yes. Inspecting and replacing worn or stretched fasteners during rebuilds is recommended to maintain proper clamping force and engine reliability.
Is this a genuine Cummins OEM fastener?
Yes. Cummins 3904217 is a genuine OEM main bearing cap bolt manufactured to factory specifications.
