CUMMINS 3925466 OEM THERMOSTAT GASKET (RECTANGULAR RING SEAL) – 5.9L 12-VALVE (1994–1998)

Product Description

The Cummins 3925466 OEM Thermostat Gasket is the correct rectangular ring-style seal used on the thermostat housing of 1994–1998 5.9L 12-Valve Cummins engines. This genuine Cummins sealing ring ensures a perfectly leak-free fit between the thermostat and the housing, helping maintain proper coolant flow, stable engine temperatures, and long-term reliability. Unlike generic aftermarket gaskets, this genuine Cummins seal delivers OE-correct compression, heat resistance, and longevity for daily-use, towing, or performance applications.

Fitment

• 1994–1998 Dodge Ram 2500/3500 with 5.9L 12-Valve Cummins (6BT)
• Replaces rectangular thermostat sealing ring on OEM thermostat housings

Cross-Reference (Cummins-Only)

Related cooling and sealing components for the 12-Valve Cummins:
• Cummins 3915787 OEM Threaded Plug – Oil Filter Housing
• Cummins 3909395 OEM Spring Hose Clamp
• Cummins 3900267 OEM Tappet Cover Bolt Grommet Seal

FAQ

Is this Cummins 3925466 gasket the correct seal for the 12-Valve thermostat?

Yes. This is the OEM rectangular ring-style gasket for the 1994–1998 5.9L 12-Valve Cummins thermostat assembly.

Can a worn thermostat gasket cause overheating or coolant leaks?

Absolutely. A damaged gasket can cause leaks, improper thermostat seating, and unstable coolant temperatures. Replacing it restores proper sealing.

Does this gasket fit 1989–1993 12-Valve engines?

No. Earlier 12-Valve engines use a different sealing design. This part is correct for 1994–1998 only.

Should this gasket be replaced when installing a new thermostat?

Yes. Cummins recommends replacing the seal anytime the thermostat is removed to ensure proper compression and leak-free operation.

Specifications for cummins 3925466