Strange Ultra Case 9" Ford Center Section
HD 40 Spline Lightweight Steel Spool
10" Pro Gear & Chrome Moly Yoke


Part Number: PRF225-10

Designed Specifically For Drag Racing
This Center Section & Gear Set May Not Fit Your Housing
Refer to the clearance diagrams shown on this page

Pro Mod
Top Dragster
Drag Radial
Outlaw 632
Radial vs The World
Radical high horsepower vehicles

• Professional assembly
• ARP ring gear bolts
• Shipped in protective container

Ultra CaseN1912
• 3.812″ bore
• 206-T4 aluminum
• Extra large oil channel
• Critical areas heavily reinforced
• Billet aluminum main caps
• Solid steel adjuster nuts
• Designed & machined by Strange
• Cast in the USA

Choice of Pinion Support

10″ Tapered Bearing SupportN1950AD
• Billet 6061-T6511 aluminum
• Drilled & tapped for 5/16″ & 3/8″ pick-up sensors
• Fits 10″ gear sets only
• Eliminates need for pinion support spacer
• Enhances rigidity
• Clear anodized finish

9″ & 9 1/2″ Tapered Bearing SupportN1950A & N1950HK
• Billet 6061-T6511 aluminum
• Drilled & tapped for 5/16″ & 3/8″ pick-up sensors
• Pinion support spacer installed for use with 10″ gears
• Provides ability to use 9″ or 9 1/2″ gears without support change
• Clear anodized finish

3/8″ Sensor Holes Were Added to Supports in 2021

HD 40 Spline Lightweight SpoolD2002
• 2.250″ bearing journal for additional load capacity
• Lightened to eliminate unnecessary weight
• Forged steel

Choice of 10″ Pro Gear

Chrome Moly Yoke & U-BoltsU1604 / U1610
• For 1350 series u-joint

Part Options
Pick-up Collar
1 magnet – U1614
2 magnet – U1614-2
4 magnet – U1614-4
8 magnet – U1614-8

9″/9 1/2″ taper/ball support w/spacer – OPRF26
Load bolt (Not for lightened gears) – N1910H
Gasket – H1111 / H1111S

Labor Options
Lighten ring gear – D3596
MicroBlue gear set – D3598G
MicroBlue gear set & bearings – OPRF42


Strange Aluminum 10 inch Gear third member with spool and Chrome Moly Yoke

The Ultra case is used where maximum gear life is essential. This case and pinion support design move both pinion bearings into the case. This offers greater support than all other designs whereas the outer bearing sits outside the case. The pinion support has a tight fit to the case bore, further eliminating any flex that can occur. This coupled with the oversized tail bearing, firmly holds the pinion gear in proper alignment with the ring gear under the most extreme conditions.

The massive billet aluminum main caps complete this maximum effort design. This case supports 9” and 9 1/2” gear sets, and can use 10” development gears with the proper pinion support. All Ultra cases have a provision to use an optional load bolt if required. Bore sizes available are 3.250” and 3.812”. The 3.812” bore Ultra case is designed for a heavy duty lightweight steel spool that features a thicker wall on the bearing journal to eliminate the possibility of collapse under the most abusive conditions.

It also allows the use of an aluminum 40 spool were applications permit. The 3.812” is available in a special lightened version with a ball bearing pinion support commonly used in Pro Stock cars. Ball bearing supports are an option on non-lighten cases as well. For a Funny car requiring a coupler cover, a support with a built-in cover is an option.

Ford 10 Inch Gears require an aftermarket Ford 9 inch third member with sufficient clearance for the larger diameter ring gear. They however have a diameter measurement of 9.4 inches. They are typically recommended for cars making around Three thousand horsepower.

The cut on these gears is engineered for maximum strength and often these gears will run with significant noise compared with a traditional Ford 9 inch gear or 9/5 inch gear.

Guidelines and Torque spec

You may also like…

  • Upgrade To Heavy Duty Cap Kit

    PN : OPRF37
    Read more
  • Upgrade Chrome Moly Yoke To 1480 Billet Yoke For Strange 9″ Ford Center Section

    PN : OPRF20
    Read more
  • D3598G-Super Finish and MicroBlue® Gear Set    Service Only - Gear Set Not Included

    Super Finish and MicroBlue® Gear Set Service Only – Gear Set Not Included

    PN : D3598G
    Add to cart
  • OPRF42-Upgrade For New Center Section    MicroBlue Gear Set, Bearings, & Races

    MicroBlue Gear Set, Bearings, & Races For Strange 9″ Ford Center Section

    PN : OPRF42
    Read more