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Stant 14539 Engine Coolant Thermostat
Heavy-Duty Cooling Control
The Stant Heavy-Duty Thermostat 14539 is an engine coolant thermostat built for consistent temperature control in demanding cooling systems. It uses a stainless steel assembly for smooth operation and is made from durable materials for long service life. This 190-degree thermostat is a direct-fit option for select BMW M5 and M6, Dodge Ram 1500, Ram 2500, Ram 3500, and Ford GT applications.
Key Features
- Part number 14539 engine coolant thermostat
- 190 Degrees Fahrenheit opening temperature
- Stainless steel assembly for smooth performance
- Durable heavy-duty construction
- Seal included
- Bypass plate diameter: 1.03 in.
- Flange diameter with seal: 2.875 in.
- Flange diameter without seal: 2.652 in.
- Height from flange to bottom: 1.45 in.
- Height from flange to top of bridge: 1.82 in.
Product Details
Stant’s Heavy-Duty Thermostat line is built for drivers who need stable coolant regulation under load. Part number 14539 opens at 190 degrees Fahrenheit and is engineered with a stainless steel assembly to promote smooth, repeatable movement. The included seal supports a proper thermostat-to-housing interface, while the heavy-duty construction is suited to vehicles that see frequent towing, performance use, or extended operating time. This thermostat is a fitment-based replacement for 2006-2008 BMW M5 and BMW M6, 2004-2006 Dodge Ram 1500, 1994-2003 Dodge Ram 2500, 1994-2003 Dodge Ram 3500, and 2006 Ford GT applications.
Common Cooling Issues Addressed
- Engine running too cool or too warm due to thermostat wear
- Slow coolant temperature stabilization after startup
- Temperature fluctuation during towing or heavy-duty use
- Cooling system service needs on select BMW, Dodge Ram, and Ford GT models
Installation Notes
Verify the 190-degree temperature specification and compare flange and bypass plate dimensions before installation. Clean the thermostat housing sealing surface thoroughly and inspect the cooling system for contamination, gasket residue, or coolant condition issues before reassembly. For fitment-specific service, confirm the vehicle application by year, make, and model: Fits 2006-2008 BMW M5, N/A; Fits 2006-2008 BMW M6, N/A; Fits 2004-2006 Dodge Ram 1500, N/A; Fits 2006 Ford GT, N/A; Fits 1994-2003 Dodge Ram 2500, N/A; Fits 1994-2003 Dodge Ram 3500, N/A.
Quality Assurance
Stant positions the Heavy-Duty Thermostat line around durable materials and stainless steel construction for dependable coolant control. Part number 14539 is built to meet the listed fitment and temperature specification for the confirmed applications above.
| Brand | Stant |
| Part Number | 14539 |
| Position | Heavy-Duty Thermostat |
| Bypass Plate Diameter (in) | 1.03 |
| Flange Diameter (With Seal) (in) | 2.875 |
| Flange Diameter (Without Seal) (in) | 2.652 |
| Freight Class | 70 |
| Height from Flange to Bottom (in) | 1.45 |
| Height from Flange to Top of Bridge (in) | 1.82 |
| Temperature (F) | 190 degrees |
This part fits 30 vehicles. Search below:
| Year | Make | Model | Position | Notes |
|---|---|---|---|---|
| 2008 | BMW | M5 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2008 | BMW | M6 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2007 | BMW | M5 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2007 | BMW | M6 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2006 | BMW | M5 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2006 | BMW | M6 | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2006 | Dodge | Ram 1500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2006 | Ford | GT | N/A | Temperature 190 Degrees; Seal Included - Seal; Alternate Temperature; Heavy-Duty Thermostat |
| 2005 | Dodge | Ram 1500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2004 | Dodge | Ram 1500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2003 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2003 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2002 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2002 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2001 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2001 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2000 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 2000 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1999 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1999 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1998 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1998 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1997 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1997 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1996 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1996 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1995 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1995 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1994 | Dodge | Ram 2500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
| 1994 | Dodge | Ram 3500 | N/A | Temperature 190 Degrees; Seal Included - Seal; OE Temperature; Heavy-Duty Thermostat |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.