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9 Inch Posi Differential Third Member, 31 Spline, 3.50 Gear Ratio

  • Based on 10 reviews
Condition: New
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$1,058.99 Why this price?

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Availability: In Stock.
Fulfilled by Speedway Motors

Arrives Sunday, Oct 18
Order within 13 hours and 11 minutes
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Size: 350


Features

  • Hand-Assembled Quality Built in-house by trained technicians using a proven step-by-step process for consistent performance, reliability, and excellent value
  • Precision Gear Setup Assembled with correct backlash, preload, and pinion shim stack to ensure an optimal ring gear tooth pattern and long service life
  • Limited Slip Performance Clutch-style positraction design delivers smooth, quiet operation with improved traction for street tires and medium horsepower applications
  • Reinforced Nodular Iron Case Heavy-duty nodular iron housing adds over 4 pounds of extra reinforcement compared to OEM gray iron for superior strength
  • Ready-to-Run Third Member Fully assembled Compatible with Ford 9-inch center section with 31-spline axles and 3.50 ratio, ideal for street-driven builds requiring dependable traction

Description

Since 1952, Speedway Motors has helped auto enthusiasts and racers build their best cars and live their best moments. Our company is full of people who, just like you, love cars and love to work on them. Whether your passion is style or performance, we are on your team to make it happen. Count on us to deliver the quality parts you need—with affordable prices, expert advice and reliable service. Way before 2-day shipping. Before 300-page catalogs, speed shops and even before seat belts, a wild bunch of the mechanically-inclined needed to go faster. That’s why in 1952, “Speedy” Bill started Speedway Motors. If "Speedy" Bill couldn’t find the right high-quality parts, he would make them himself. Today, we stock and manufacture automotive parts so you can build what you want. Our products are designed, built, and packaged by our very own car enthusiasts who just like you, love cars.

Manufacturer: ‎Speedway Motors


Brand: ‎Speedway Motors


Model: ‎Speedway Motors


Item Weight: ‎87 pounds


Product Dimensions: ‎18 x 14.3 x 13.4 inches


Item model number: ‎91049345-31-350


Exterior: ‎Machined


Manufacturer Part Number: ‎91049345-31-350


Position: ‎Center


Date First Available: January 29, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Oct 18

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
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  • Zip Pay in 4
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  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Badass
Size: 370
Ty
Reviewed in the United States on March 4, 2026 by Amazon Customer

  • 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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