Product Description
Cummins 3908082 — Intake Manifold Cover / Inlet (3.9L 4BT)
MPN: 3908082 | Also Known As: intake manifold cover, intake crossover inlet | Engine Family: B Series 3.9L (4BT)
Why This Part
- ✓ OE cast inlet/cover for the 3.9L 4BT intake plenum.
- ✓ Direct-fit replacement built to Cummins specs for proper airflow and sealing.
- ✓ Ideal for restorations, step-van service, and 4BT swaps where factory geometry matters.
- ✓ Durable casting designed for industrial-duty reliability.
Quick Specs
| Type | Intake manifold cover / cast inlet |
|---|---|
| OE Part # | 3908082 |
| Engine | B Series 3.9L (4BT) |
| Qty Required | 1 per engine (sold individually) |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1989–1998 | Cummins 3.9L 4BT (B Series) | Step Van / Box Truck (varies by OEM) |
Industrial/Off-Highway: Used primarily on BS3 3.9L B engines in power-gen and industrial equipment—verify by ESN before ordering.
Often Paired With
- Intake Manifold/Plenum Gasket: 3938153 (replaces 3914028) — verify by ESN
- Charge-air boot & clamps: sized to your inlet plumbing (verify diameter)
What’s In The Box
- (1) Genuine Cummins Intake Manifold Cover / Inlet (3908082)
- Gasket, boot, and clamps sold separately.
Install Tips
- Clean the plenum sealing surface; use a new gasket and proper torque sequence.
- Inspect boots & clamps for wear; pressure-test the charge system after install.
- Confirm part by Engine Serial Number (ESN) for industrial applications.
FAQ
WILL THIS FIT MY 3.9L 4BT?Yes—this is the OE intake manifold cover/inlet for the B Series 3.9L (4BT). Automotive fitment commonly spans 1989–1998 step-van/box-truck applications; always verify by ESN.
DOES THIS INCLUDE THE INTAKE GASKET?No—the gasket is sold separately. Common references include 3938153 (replaces 3914028); confirm by ESN.
WHAT ABOUT 5.9L 6BT/ISB ENGINES?This listing targets the 3.9L 4BT. 5.9L engines use different inlets/covers—search by your exact ESN.
IS THIS A GENUINE CUMMINS PART?Yes—OE Cummins 3908082 built to factory specifications.
WHAT’S THE INLET SIZE?Most listings describe a ~2.0" OD inlet; confirm against your charge pipe before ordering.
