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Westar ST-7939 Coil Spring Insulator - Front Upper
Front Upper Coil Spring Insulator for Explorer
Restore proper suspension isolation and mounting support with the Westar ST-7939 coil spring insulator. This front upper suspension component is built for 2006-2010 Ford Explorer, 2007-2010 Ford Explorer Sport Trac, and 2006-2010 Mercury Mountaineer applications, helping maintain correct suspension movement while reducing road noise and vibration.
Key Features
- Provides a pivot point for the suspension to rotate on, helping maintain correct suspension dynamics
- Helps support steering response and reduce uneven tire and component wear
- Locks the strut and body together for secure front upper mounting
- Includes a noise-dampening function to reduce road noise and vibration transfer into the cabin
- Westar ST-7939 is built with application-specific materials and a protective finish for durability
Detailed Description
The Westar ST-7939 coil spring insulator is a front upper suspension part designed for Ford Explorer, Ford Explorer Sport Trac, and Mercury Mountaineer models listed in the fitment data. By isolating the spring and supporting the strut assembly, it helps preserve suspension geometry and reduce harshness from the road. This part cross-references Monroe Shocks & Struts (e.g., 907939) for the same application.
Use Westar ST-7939 when servicing the front upper suspension on 2006-2010 Ford Explorer, 2007-2010 Ford Explorer Sport Trac, or 2006-2010 Mercury Mountaineer vehicles. The part number ST-7939 is also useful when searching for an OE-style replacement for these front upper applications.
Common Issues This Part May Address
- Clunking or squeaking from the front upper suspension area
- Excess vibration transmitted through the strut mount area
- Loss of proper suspension rotation at the upper mount point
- Premature tire or suspension component wear related to mounting movement
- Loose or degraded upper strut-to-body connection
Installation Notes and Tips
Install ST-7939 only on the listed front upper applications. Inspect the surrounding strut, spring, and mounting components before installation, and replace worn related parts as needed to restore proper suspension operation. Verify vehicle year, make, model, and position before ordering to ensure correct application.
Quality Assurance
Westar states that this part is made with application-specific materials and finished to help extend service life while maintaining a clean appearance. The ST-7939 is engineered for the listed suspension applications and built to support consistent fit and function.
| Brand | Westar |
|---|---|
| Part Number | ST-7939 |
| Bullet 1 | Provides a pivot point for the suspension to rotate on, to allow |
| Bullet 2 | Provides a locking mechanism to lock the strut and body together |
| Bullet 3 | Provides a noise dampening system to prevent noise and vibrations |
This part fits 14 vehicles. Search below:
| Year | Make | Model | Position | Notes |
|---|---|---|---|---|
| 2010 | Ford | Explorer | Front Upper | |
| 2010 | Ford | Explorer Sport Trac | Front Upper | |
| 2010 | Mercury | Mountaineer | Front Upper | |
| 2009 | Ford | Explorer | Front Upper | |
| 2009 | Ford | Explorer Sport Trac | Front Upper | |
| 2009 | Mercury | Mountaineer | Front Upper | |
| 2008 | Ford | Explorer | Front Upper | |
| 2008 | Ford | Explorer Sport Trac | Front Upper | |
| 2008 | Mercury | Mountaineer | Front Upper | |
| 2007 | Ford | Explorer | Front Upper | |
| 2007 | Ford | Explorer Sport Trac | Front Upper | |
| 2007 | Mercury | Mountaineer | Front Upper | |
| 2006 | Ford | Explorer | Front Upper | |
| 2006 | Mercury | Mountaineer | Front Upper |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.