Product Description
Interstate-McBee M-3958644 Multi-Layer Thin Head Gasket – 03–07 5.9L Cummins (Aftermarket Replacement)
High-quality multi-layer steel (MLS) thin head gasket for 2003–2007 Dodge Ram 2500/3500 with the 5.9L Cummins 24-valve common-rail (ISB). Designed for OE-equivalent sealing with proper surface prep and torque procedure. Sold individually.
- MLS construction: Durable multi-layer steel for consistent clamp load and sealing.
- Thin profile: Helps maintain compression ratio and quench compared to thicker service gaskets.
- Direct fit: Built to OE form/fit for straightforward installation.
- Interstate-McBee quality: Trusted aftermarket replacement for Cummins applications.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3958644 |
| OEM Reference | Cummins 3958644 |
| Gasket Type | Multi-Layer Steel (MLS), thin |
| Sold As | Each (1 head gasket) |
| Position | Cylinder head to engine block |
Vehicle Fitment
Always verify by engine serial number (ESN) when possible.
- Dodge Ram 2500/3500 5.9L Cummins (24-valve common-rail)
- Model Years: 2003–2007
- Engine: ISB 5.9L (common-rail)
What’s Included
- (1) Interstate-McBee M-3958644 MLS thin head gasket
Recommended/Related Parts
- New head bolts or head studs (replace torque-to-yield bolts; follow manufacturer instructions)
- Clean, flat cylinder head and block surfaces (check for warp)
- Intake/exhaust manifold gaskets, valve cover gasket, coolant and oil as needed
Install Notes
- Confirm correct gasket thickness for your application before installation.
- Surface finish matters: target a smooth, even RA per Cummins service guidance.
- Do not use sealant on MLS head gaskets unless specifically called for by the manufacturer.
- Follow the Cummins torque sequence and stages; re-torque only if the procedure specifies.
- After assembly, bleed cooling system and verify no combustion gases in coolant.
Why Buy From CPP Diesel
- ESN-verified fitment help from diesel specialists
- Fast shipping and competitive pricing
- Deep inventory for your complete top-end refresh
FAQ
Is this the correct gasket for my 2003–2007 5.9L?
Yes—this listing covers 2003–2007 5.9L Cummins common-rail engines used in Ram 2500/3500. For certainty, verify by ESN.
What does “thin” mean here?
It refers to the thinner MLS variant compared to thicker service gaskets. Thinner gaskets help maintain factory compression and quench. Confirm thickness required for your build.
Do I need new head bolts?
Yes—replace torque-to-yield bolts or upgrade to studs. Follow the fastener manufacturer’s instructions for torque values and lubricant.
Does this fit 1998.5–2002 24-valve or 6.7L engines?
No. This gasket is specific to 2003–2007 5.9L common-rail applications.
