Product Description
The CUMMINS 3958645 OEM CYLINDER HEAD GASKET (THICK) is designed for 2003–2007 Dodge Ram trucks equipped with the 5.9L Common Rail Cummins diesel engine. This genuine Cummins head gasket is engineered to provide a reliable seal between the cylinder head and engine block while maintaining proper compression, coolant flow, and oil passage sealing.
Use this gasket when replacing a damaged head gasket, performing cylinder head service, or rebuilding a 5.9L Cummins engine. Always verify fitment and required gasket thickness before ordering.
FEATURES
- Genuine Cummins OEM cylinder head gasket
- Thick gasket configuration
- Direct-fit replacement for 5.9L Common Rail Cummins engines
- Helps maintain proper compression and sealing integrity
- Designed to withstand diesel combustion pressures and temperatures
- Ideal for engine repair, cylinder head service, and rebuild projects
FITMENT
- 2003–2007 Dodge Ram 2500 5.9L Cummins Common Rail
- 2003–2007 Dodge Ram 3500 5.9L Cummins Common Rail
- Select Cummins ISB 5.9L applications requiring thick head gasket specification
WHAT'S INCLUDED
- 1 Cummins 3958645 OEM Cylinder Head Gasket (Thick)
CROSS-REFERENCE AND RELATED PRODUCTS
- Cummins 3958645
- Cummins Cylinder Head Bolts
- Cummins Top End Gasket Sets
- Cummins Valve Cover Gaskets
SPECIFICATIONS
- Manufacturer: Cummins
- Part Number: 3958645
- Part Type: Cylinder Head Gasket
- Configuration: Thick
- Engine Compatibility: 5.9L Cummins Common Rail
- Fitment Years: 2003–2007
- Vehicle Application: Dodge Ram 2500 / 3500
- Condition: New OEM Cummins
- Installation Type: Direct Replacement
- Location: Between Cylinder Head and Engine Block
FAQ
Will this part fit my truck?
This gasket fits many 2003–2007 Dodge Ram 2500 and 3500 trucks equipped with the 5.9L Common Rail Cummins engine. Always verify fitment and gasket thickness requirements before ordering.
Is this a genuine Cummins gasket?
Yes. Cummins 3958645 is a genuine OEM Cummins cylinder head gasket designed to meet factory sealing specifications.
What does the thick designation mean?
The thick version is intended for applications requiring that specific gasket thickness based on piston protrusion and engine build specifications.
Should head bolts be replaced during installation?
Inspect all head bolts and fasteners during installation. Many engine builders recommend replacing torque-to-yield fasteners or upgrading to performance head studs when appropriate.
What are the signs of a failed head gasket?
Common symptoms include coolant loss, overheating, combustion gases in the cooling system, white exhaust smoke, or loss of engine compression.
Do I need any related parts?
Inspect the cylinder head, head bolts or studs, valve cover gasket, intake and exhaust manifold gaskets, and cooling system components during installation and replace worn parts as necessary.
