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Posi Differential 3rd Member for Ford 9 Inch, 28 Spl, 3.70 Gear Ratio

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$949.99

$ 99 .00 $99.00

In Stock
  • 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 ford 9 inch limited slip differentials
  • 9 inch 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!)


As featured on Classic Truck’s Week to Wicked. Watch the transformation here! Assembled by Professionals Hand-assembled by trained experts in-house, ourCompatible with Ford 9-inch third members are built from quality components with an exact step-by-step process. We bring this combination of precision assembly and quality components to you at a price that can’t be beat. We trust these third members so much, they’re the go-to choice for our own rides, from the street to the track. Tough, Nodular Iron Center Section OurCompatible with Ford 9 Inch Nodular Iron Third Member Center Section Carrier starts with a NEW casting with over 4 lbs. of additional material in critical areas. Nodular (ductile) iron is much more resistant to fracturing than OEM “gray” iron. Extra ribbing reinforces the case and rearmost pinion support (pilot bearing). Thick, forged steel bearing caps surround the carrier bearings, all securely held in place with precision Grade 8 cap screws. The improvements continue with rugged billet steel adjuster nuts and heavy-duty keepers to ensure your ring gear settings are maintained. All mounting surfaces are precision machined to ensure a consistent, flat surface for a positive gasket seal (no more leaks on your shop floor). An oil fill plug is included. Precision Assembled for Proper Ring Gear Teeth Pattern Getting a proper pattern on the ring gear teeth is crucial. Our time-proven, step-by-step process ensures the correct backlash, preload, and proper amount of pinion shims to ensure the correct pattern on the ring gear teeth. Our gears use cold-rolled 8620 steel, known for its long-wear and durability. To ensure a proper gear pattern, we use a stronger “Daytona” style pinion bearing support to maintain that critical pinion depth setting


Ashley Smith
Reviewed in the United States on May 29, 2024
I’ve got ~1500 miles on this thing and I’m already having to pull and replace it. It’s whined and roared since I installed it, and speedway assured me it would get better as it broke in. I knew they were full of it, and sure enough, it only got worse the longer I drove it. Not only has it gotten louder, it shudders and grinds so bad when I turn now, it feels like it’s gonna come apart. It’s not even worth shipping back considering what the shipping costs are, and I don’t trust them to be able to fix it considering what an absolutely abysmal job they did assembling it in the first place. Lesson learned, you get what you pay for…and sometimes not even that.
Jack Ryland
Reviewed in the United States on April 8, 2024
I installed the part. Test drove the car differential is making a loud whining noise.Would like a replacement.