CUMMINS 3973853 OEM VALVE COVER BOLT VIBRATION ISOLATOR / SEAL – RAM 5.9L/6.7L (2006–2024)

Product Description

The Cummins 3973853 OEM Valve Cover Bolt Vibration Isolator / Seal is the factory-correct rubberized isolator that fits over the valve cover bolts on 2006–2024 Ram 2500/3500/4500/5500 trucks equipped with the 5.9L or 6.7L Cummins. This isolator controls bolt vibration, protects the valve cover, and ensures proper sealing around each fastener. Over time, these dampers can crack, harden, or deform from heat cycles—resulting in oil seepage or uneven valve cover compression. Replacing them with genuine Cummins hardware restores OEM fit, quiet operation, and long-term durability.

Fitment

• 2006–2007 Dodge Ram 2500/3500 with 5.9L ISB Cummins
• 2007.5–2024 Ram 2500/3500/4500/5500 with 6.7L Cummins
• Used on OEM-style valve covers requiring Cummins vibration isolator bushings

Cross-Reference (Cummins-Only)

Related sealing and valve cover hardware components:

• Cummins 3900267 Tappet Cover Bolt Grommet Seal
• Cummins 3904409 Valve Stem Guide – 12V
• Cummins 3909395 Dipstick Spring Clamp

FAQ

What does the Cummins 3973853 vibration isolator do?

This isolator reduces vibration at the valve cover bolts while sealing the bolt through-holes to prevent oil weeping.

Should these isolators be replaced when installing a new valve cover gasket?

Yes. Heat and pressure cycles harden the rubber over time. Replacing them ensures proper sealing and even bolt load.

Does this part fit both 5.9L and 6.7L Cummins engines?

Yes. It fits 2006–2007 5.9L and all 6.7L Cummins engines from 2007.5–2024.

How many isolators does the valve cover use?

Most OEM covers use six or more, depending on model year and cover design. Replace all isolators for best results.

Specifications for cummins 3973853