USA Standard Gear

31 Spline 29.25" Rear Axle

$256.98

SKU: ZA FM4235B

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

Description

The USA Standard Gear ZA FM4235B rear axle is engineered for precision and durability, specifically for the Ford 8.8-inch rear end found in 1979-1993 Mustangs. This axle is built to withstand the demands of both street and track use, offering a robust solution for drivetrain upgrades. Key specifications include a 31 spline configuration, which ensures compatibility with high-performance applications and requires a 31 spline carrier for integration. The 4-lug design facilitates easy fitment with factory wheels, and the overall length of 29.25 inches is crucial for proper installation and alignment. These features contribute to a reliable and direct-fit replacement or upgrade for your Mustang's rear end. Installation notes specify that these aftermarket axles require a 31 spline carrier. It is important to verify your existing setup meets this requirement for optimal performance. The product is backed by a 5-year warranty against manufacturer defects, offering peace of mind for your investment.

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

BrandUSA Standard Gear
Part NumberZA FM4235B
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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