CUMMINS 3904409 OEM VALVE STEM GUIDE – 51.75MM – 5.9L 12-VALVE (1989–1998)

Product Description

The Cummins 3904409 OEM Valve Stem Guide (51.75mm) is a direct-fit, genuine Cummins valvetrain component engineered to restore precise valve movement and long-term sealing performance in your 1989–1998 5.9L 12-Valve 6BT engine. Manufactured to exact OEM tolerances, this stem guide delivers optimal oil control and correct valve alignment — critical for reliability in stock, towing, and performance applications. If you're completing a cylinder head refresh or a full engine build, this genuine Cummins guide ensures durability far beyond aftermarket substitutes.

Fitment

• 1989–1998 Dodge Ram 2500/3500 with 5.9L 12-Valve Cummins (6BT)
• Compatible with OEM cylinder heads requiring 51.75mm valve stem guide length

Cross-Reference (Cummins-Only)

For related Cummins 12-Valve valvetrain components, see:
• 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

What is the correct length of this Cummins 3904409 valve stem guide?

The 3904409 guide measures 51.75mm and is used on OEM 12-Valve cylinder heads requiring the shorter intake/exhaust guide length.

Should valve stem guides be replaced during a head rebuild?

Yes. Worn guides cause oil consumption, poor sealing, and premature valve wear. Replacing them with genuine Cummins components ensures correct clearances and long service life.

Is machining required when installing OEM Cummins valve stem guides?

A machine shop typically handles pressing and sizing the new guides to meet OEM specifications for valve stem-to-guide clearance.

Can this guide be used with performance valves or springs?

Yes — as long as the cylinder head maintains OEM dimensions. Genuine Cummins guides remain the most reliable option for performance or towing builds.

Specifications for cummins 3904409