Zumbrota Drivetrain

Ford 9" 31 Spline Spool

$186.89

SKU: ZP FSF9-31

In Stock
In Stock
Ships by Aug 31
Free Shipping over $200
$100 Minimum Order
30 Days Return

Description

The USA Standard spool is a drivetrain component specifically designed to fit Ford 9" differentials that utilize 31 spline axles. This spool is engineered to deliver 100% traction to both wheels simultaneously, ensuring maximum grip in off-road or performance driving conditions. While it offers significant traction benefits, this spool is explicitly not recommended for street-driven vehicles due to its constant locked differential action. This type of setup can cause tire scrubbing, increased wear, and compromised handling on paved surfaces. It is best suited for off-road applications, racing, or specialized builds where maximum traction is the primary requirement. Further technical specifications include a shipping weight of 7.8300 LB and dimensions of 8.00 x 8.00 x 7.00 inches. The product is manufactured by USA Standard Gear and carries the UPC 883584590040. Buyers are also advised of California Proposition 65 warnings regarding potential exposure to chemicals.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandZumbrota Drivetrain
Part NumberZP FSF9-31
CategoryDrivetrain

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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