FOX SEAL DRIVER 40MM
The Professional Standard for Suspension Service.
The Fox Fork Seal Driver is a precision-engineered shop tool designed for the flawless installation of dust wipers on Fox suspension forks. Specifically sized for 40mm stanchions—the hallmark of the legendary Fox 40 dual-crown downhill fork—this tool ensures that seals are seated perfectly level and at the correct depth every time.
Using a dedicated driver is the only way to avoid the common pitfalls of suspension DIY, such as cocked seals that lead to premature leaking or damage to the delicate outer lip of the wiper. Whether you are a professional mechanic or a dedicated gravity rider performing your own 50-hour "lowers" service, this tool is the difference between a leaky fork and a factory-smooth feel.
Key Performance Features
Precision Fit: Specifically machined to the exact tolerances of 40mm Fox Dust Wiper seals, providing a snug fit that prevents the tool from slipping during installation.
Pilot Hub Design: Features a central guide that slides over the stanchion (or into the lower leg) to ensure the seal is driven perfectly square into the fork bore.
Impact-Resistant Material: Constructed from a high-density, non-marring polymer that is tough enough to take mallet strikes while remaining gentle enough to protect the finish of your fork lowers.
Optimal Depth Control: The shoulder of the tool is designed to stop once the seal has reached its factory-specified seating depth, eliminating the guesswork from the assembly process.
Ergonomic Grip: The textured body provides a secure hold, even when your hands are covered in 20wt Gold oil or suspension grease.
Knurled Strike Surface: Provides a flat, stable area for your dead-blow mallet, ensuring all force is transferred directly and evenly to the seal.
Technical Specifications
| Feature | Specification |
| Compatible Stanchion Size | 40mm (Fox 40 Series) |
| Material | High-Strength Reinforced Polymer |
| Part Number | 398-00-771 |
| Application | Dust Wiper & Oil Seal Installation |
| Compatibility | Flanged and Flangeless Seals |
✅ Why This IS For You
The Downhill Racer: If you own a Fox 40, you know that keeping your seals fresh is vital for small-bump sensitivity. This tool pays for itself after just two home services.
The Home Mechanic: Essential if you want to perform a factory-level service without risking damage to expensive lower legs or stanchions.
Workshop Efficiency: For the shop environment, this tool saves time and reduces the risk of "re-work" caused by improperly seated seals.
❌ Why This May NOT be for you
Single Crown Riders: This tool is strictly for 40mm stanchions. If you are servicing a Fox 32, 34, 36, or 38, you will need the specific driver size corresponding to those models.
"MacGyver" Mechanics: While some riders use PVC pipe as a makeshift driver, it lacks the precision pilot guide and depth stop, significantly increasing the risk of a crooked seal and oil leaks.
BFC Pro Tip
Before driving the new seals in, always apply a light coating of Fox 20wt Gold Oil or Slick Honey to the outer diameter of the seal and the inner bore of the fork lowers. This reduces friction and allows the seal to slide into place smoothly. When using the driver, use a dead-blow mallet rather than a standard metal hammer; the dead-blow provides a "thud" that seats the seal without the jarring vibration that can cause the tool to bounce. Stop immediately once the sound of the strike changes from a hollow "clack" to a solid "thump"—that’s how you know you’ve hit the bottom!





