Strange S-Trac 9" Ford 35 Spline Differential


Part Number: N1980

Ford 9″ with 35 spline axles

3.250″ bore aftermarket case
Axles with 30 degree pressure angle

Strange 35 Spline S-Trac
This helical gear differential offers smooth and progressive power transfer
Superior design and quality make it ideal for the most abusive Street/Track applications

Torque Biased Mechanical Unit
• Helical gear design
• Maximizes traction and acceleration
• Dependable and maintenance free
• Quiet operation

Forged Steel Case Halves
• Heat treated
• Fully machined
• Provides a light, durable, and rigid unit

Internal Gear Pocket Geometry
• Minimizes stress risers
• Increases service life

Dry Film Solid Lubricant Coating
• Applied to thrust surfaces
• Minimizes component wear

9310 Steel Pinion Gears
• Chrome moly material
• Provides the ultimate in torque carrying capacity

Aggressive Gear Helix Angle
• Promotes superior torque bias
• Excels in situations of unequal traction

All Internal Gears Made from 9310 Steel
• Vacuum heat treated for superior strength
• Additionally cold treated to optimize fatigue life and reduce wear

Proven Quality
• Designed, machined, & assembled by Strange
• Materials made in the USA

Do Not Use Synthetic Gear Oil or Posi Additive
Will adversely affect unit operation
Voids all manufacturer warranties

Use Petroleum Based 80W-90 or 85W-140

S-Series 3.250″ bore case – N2206
Pro Iron 3.250″ bore case – N1906
Pro HD Aluminum 3.250″ case kit – P3203

Side bearing kit – D1590

Alloy axle package – P3502 / P3504


Strange Helical Differential For Ford 9in

The Strange 35 Spline S-Trac Differential is a helical differential that offers smooth and progressive power transfer. Its superior design and quality make it ideal for the most abusive Street/Track applications. The torque biasing S Trac Differential is purely mechanical which eliminates the need for clutches. It provides quiet operation while maximizing tire traction and vehicle acceleration.

The Strange Helical Differential

Built with forged steel case halves that are heat treated and fully machined to minimize weight and provide a rigid mounting surface for the ring gear resulting in improved gear life. Internal gear pocket geometry is designed to minimize stress risers increasing component life. The housing encapsulates precision manufactured gears, including 9310 steel pinion gears, that provide exceptional strength. All internal gears, pinion and side gears, are vacuum heat treated to increase strength and also cold treated to extend service life while reducing wear. A dry film solid lubricant coating is applied to friction surfaces to minimize wear.

Ideal for road racing, off-road and autocross applications.

The S Trac Helical Differential is recommended for full bodied street/track cars that run the 1/4 mile in the low 9 seconds or slower. For Drag Race Only vehicles, Strange Engineering recommends using a spool. The seamless operation also makes it ideal for road racing, off-road and autocross. This premium differential unit carries a limited lifetime replacement warranty to the original purchaser.

Parts List and Installation Guide pdf File

You may also like…

  • N2206-Strange S-Series 9" Case  Nodular Iron - 3.250" Bore

    Strange 9″ Nodular Iron Case S-Series – 3.250″ Bore

    PN : N2206
    Add to cart
  • D1592-Side Bearing Kit  Strange S60  Ford 9" with 3.812" Bore Case

    Side Bearing Kit Ford 9″ with 3.250″ Bore Case

    PN : D1590
    Add to cart
  • N1906-Strange Pro Series 9" Case Nodular Iron - 3.250" Bore

    Strange 9″ Ford Nodular Iron Case Pro Series – 3.250″ Bore

    PN : N1906
    Add to cart
  • P3207BB-Strange HD Pro Aluminum Case Kit  3.812" Bore With Tapered / Ball Bearing Support

    Strange HD Pro Aluminum Case and Support Kit 3.250″ Bore With Tapered Bearing Support

    PN : P3203
    Add to cart