CUMMINS 3906854 OEM INTAKE VALVE SEAT INSERT – 5.9L 12-VALVE (1989–1998)

Product Description

The Cummins 3906854 OEM Intake Valve Seat Insert restores proper valve sealing, heat transfer, and long-term reliability in the 1989–1998 5.9L 12-Valve 6BT cylinder head. This is a genuine Cummins hardened intake seat engineered to maintain precise fitment and durability under high combustion temperatures, making it the only correct choice for engine rebuilds, head refurbishing, or performance/towing upgrades. Using OEM valve seat inserts ensures consistent valve sealing, prevents premature valve burn, and supports stable compression across all cylinders.

Fitment

• 1989–1998 Dodge Ram 2500 / 3500 with 5.9L 12-Valve 6BT Cummins
• Designed specifically for OEM 12-Valve cylinder heads (intake side)

Cross-Reference (Cummins-Only)

Pair this intake valve seat insert with additional Cummins 12-Valve valvetrain components:
• Cummins 3904409 OEM Valve Stem Guide – 51.75mm
• Cummins 3904408 OEM Valve Stem Guide – 60.50mm
• Cummins 3903924 OEM Timing Pin – 5.9L 12-Valve
• Cummins 3900267 Tappet Cover Bolt Grommet Seal

FAQ

Is this Cummins 3906854 valve seat insert for the intake or exhaust side?

This part is specifically the intake valve seat insert for 12-Valve 5.9L Cummins cylinder heads.

Should the valve seats be replaced during a head rebuild?

Yes. Replacing worn valve seat inserts ensures proper valve sealing, prevents valve burning, and restores consistent compression.

Does this valve seat require machining for installation?

Yes, OEM-spec installation requires a machine shop to properly remove the old seat, machine the counterbore, install the new insert, and cut the correct valve angle.

Can genuine Cummins valve seats be used in performance builds?

Absolutely — hardened OEM Cummins inserts provide superior durability for towing, hot-shot, and performance applications.

Specifications for cummins 3906854