Product Description
Interstate-McBee M-3969988 Intake Horn / Grid Heater Gasket – 94–07 5.9L Cummins
Direct-replacement gasket for the joint between the intake horn and the grid heater plate on 1994–2007 Dodge Ram trucks equipped with the 5.9L Cummins. Designed to seal boost pressure and prevent unmetered air leaks. Sold individually.
- OE-style fit: Matches Cummins reference 3969988 for proper sealing at the intake horn/grid heater interface.
- Durable material: Quality construction suitable for stock boost levels and daily use.
- Maintenance-friendly: Ideal when servicing grid heaters, intake horns, or performing manifold work.
- Value: Interstate-McBee aftermarket replacement for reliable performance at a fair price.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3969988 |
| OEM Reference | Cummins 3969988 |
| Component | Intake horn / grid heater gasket |
| Sold As | Each (1 gasket) |
| Position | Between grid heater plate and intake horn |
What’s Included
- (1) Intake horn / grid heater gasket, P/N M-3969988
Vehicle Fitment
Always verify by engine serial number (ESN) or OEM part reference when possible.
- Dodge Ram 2500/3500 – 5.9L Cummins
- Model Years: 1994–2007
- Engines: 12-valve (1994–1998) and 24-valve (1998.5–2007)
- Other B-Series applications where Cummins 3969988 is specified.
Recommended/Related Service Items
- Grid heater plate hardware (inspect/replace as needed)
- Intake horn clamps/boots
- MAP/IAT sensor O-rings if removed during service
Install Notes
- Clean both mating surfaces thoroughly; remove old gasket material and residue.
- Dry-fit to confirm orientation. No sealant typically required unless specified by the service manual.
- Tighten fasteners evenly in a criss-cross pattern to factory torque.
- After installation, pressure-test or road-test to verify no boost leaks.
Why Buy From CPP Diesel
- Diesel specialists with ESN-verified fitment support
- Fast shipping and easy returns
- Large inventory of complementary Cummins intake and seal components
FAQ
Do I need more than one gasket?
No. One gasket seals the joint between the grid heater plate and the intake horn.
Will this fit both 12-valve and 24-valve 5.9L engines?
Yes—this listing covers 1994–1998 (12V) and 1998.5–2007 (24V) trucks where Cummins 3969988 is specified. Verify by ESN if unsure.
Should I use sealant?
Typically not. Follow the Cummins service manual; most installations use a clean, dry gasket on clean surfaces.
