Product Description
Genuine Cummins
Cummins 3925466 — Thermostat Gasket / Rectangular Ring Seal
MPN: 3925466 | Also Known As: thermostat gasket, rectangular ring seal | Position: Thermostat-to-housing seal
Why This Part
- ✓ OE sealing ring for reliable thermostat housing seal.
- ✓ Direct-fit for 1994–1998 5.9L 12-valve Cummins (2nd Gen).
- ✓ Helps prevent coolant leaks/overheating after service.
- ✓ One per service; replace anytime the housing is removed.
OE Fit Stock Replacement 1 Per Service
Quick Specs
| Type | Thermostat gasket / rectangular ring seal |
|---|---|
| OE Part # | 3925466 |
| Qty Required | 1 per service (sold individually) |
| Often Paired | Thermostat 3928499 • Housing cover gasket 3927305 |
Verified Fitment (Automotive)
| Year Range | Engine | Chassis |
|---|---|---|
| 1994–1998 | 5.9L Cummins 12-Valve (2nd Gen) | Dodge Ram 2500/3500 |
Industrial/Off-Highway: Also seen on certain Euro II 5.9B applications; confirm by ESN.
Often Paired With
- Thermostat: Cummins 3928499 (180°)
- Thermostat housing cover gasket: Cummins 3927305
- Coolant top-off and burp procedure after service
What’s In The Box
- (1) Genuine Cummins Thermostat Gasket / Rectangular Ring Seal (3925466)
- Hardware/thermostat sold separately (see “Often Paired With”).
Install Tips
- Clean and dry mating surfaces; remove old seal residue.
- Seat gasket evenly; torque housing fasteners to spec.
- Refill coolant, bleed air, and verify no leaks on warm-up.
FAQ
WILL THIS FIT MY 1994–1998 5.9L 12-VALVE RAM?Yes—3925466 is the OE thermostat gasket for most 1994–1998 5.9L 12-valve applications (verify by VIN/ESN).
DO I NEED TO REPLACE THIS EVERY TIME I OPEN THE HOUSING?Yes—replace the gasket whenever the thermostat housing is removed to ensure a proper seal.
WHAT OTHER PARTS SHOULD I ORDER?Common pairings are thermostat 3928499 (180°) and housing cover gasket 3927305.
IS THIS A GENUINE CUMMINS PART?Yes—OE Cummins gasket with correct dimensions for the 5.9L 12-valve thermostat housing.
WILL THIS FIT 24-VALVE OR 6.7L ENGINES?This listing targets 12-valve (1994–1998). Later engines use different gaskets—verify by VIN/ESN.
