Product Description
Interstate-McBee M-3999820 Crankcase Breather Gasket — 07.5–18 6.7L Cummins (Aftermarket Replacement)
Replacement crankcase breather (CCV) gasket for 2007.5–2018 6.7L Cummins ISB applications. Seals the breather housing to the valve cover to prevent oil mist and crankcase vapors from leaking. Sold individually.
- Direct replacement: OE-style fit and function for a leak-free seal.
- Durable materials: Designed to withstand heat, oil, and crankcase vapor exposure.
- Maintenance friendly: Ideal to replace whenever the CCV filter or breather assembly is serviced.
- Value: Interstate-McBee quality at a budget-friendly price.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3999820 |
| OEM Reference | Cummins 3999820 |
| Component | Crankcase Breather (CCV) Gasket |
| Location | Between CCV/breather housing and valve cover |
| Sold As | Each (1 gasket) |
What’s Included
- (1) Crankcase breather gasket, P/N M-3999820
Vehicle Fitment
Verify with your engine serial number (ESN) for best accuracy.
- Ram 2500/3500 with 6.7L Cummins ISB — Model Years: 2007.5–2018
- Ram 3500/4500/5500 Chassis Cab with 6.7L Cummins — Model Years: 2008–2018 (verify by ESN)
- Other 6.7L Cummins ISB applications specifying Cummins 3999820
Recommended/Related Parts
- Crankcase (CCV) Filter/Element — replace with the gasket for best results
- Breather housing hardware/seals as required
- Valve cover perimeter gasket (inspect and replace if needed)
Install Notes
- Remove the breather/CCV housing and clean mating surfaces thoroughly; avoid debris entry.
- Install the new gasket dry (no RTV unless specified by the service manual).
- Tighten fasteners evenly in a cross pattern to the factory torque spec.
- Replace the CCV filter if due; reset any maintenance indicators per the vehicle procedure.
Why Buy From CPP Diesel
- Diesel specialists with ESN-verified fitment support
- Fast shipping and easy returns
- Deep inventory of Cummins gaskets, seals, and maintenance parts
FAQ
When should I replace this gasket?
Any time you service the CCV filter or remove the breather housing, and whenever you notice oil mist seepage around the housing.
Is sealant required?
Generally no—install the gasket dry on clean surfaces. Follow your Cummins/vehicle service manual if a specific sealant is called out.
How do I confirm fitment?
Match to Cummins reference 3999820 or provide your ESN to confirm compatibility.
