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Posi Differential 3rd Member for Ford 9 in, 31 Spl, 3.50 Gear Ratio

  • Based on 4 reviews
Condition: New
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$978.99 Why this price?

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Availability: In Stock.
Fulfilled by Speedway Motors

Arrives Jul 24 – Jul 29
Order within 7 hours and 17 minutes
Available payment plans shown during checkout

Size: 350


Features

  • Hand-assembled by our trained technicians for an unbeatable combination of quality and value
  • Precision assembly for the correct backlash, preload, and proper amount of pinion shims to ensure the correct pattern on the ring gear teeth on all of our Compatible with Ford 9 inch limited slip differentials
  • 9 inch Compatible with Ford posi units are ideal for street tires and medium horsepower applications
  • Nodular iron housing is stronger than OEM gray iron and has 4 lbs of additional reinforcement
  • Clutch style positraction differential gives limited slip performance and quiet operation (no gears clicking!)

Manufacturer: ‎Speedway Motors


Brand: ‎Speedway Motors


Model: ‎Speedway Motors


Item Weight: ‎87 pounds


Product Dimensions: ‎18 x 14.3 x 13.4 inches


Manufacturer Part Number: ‎91049345-31-350


Date First Available: January 29, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Jul 24 – Jul 29

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Third member
Size: 411
Speedway did not pay me back for all of the purchase
Reviewed in the United States on February 25, 2024 by Tracy Earl

  • Noisy
Size: 350
Rear differential makes noise on Decel, toe and heel pattern not set correctly.
Reviewed in the United States on April 9, 2023 by Kennie a Reimer

  • Noisy and leaks
Size: 370
Not set up correctly, howls on deceleration, pinion seal leaks. Not worth it at all.
Reviewed in the United States on January 8, 2025 by Cody

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