Posi Differential 3rd Member, 31 Spl, 3.70 Gear Ratio, Fits Ford 9 Inch

Description: Expert Craftsmanship: Hand-assembled by skilled technicians, ensuring unmatched quality and value, perfect for medium horsepower street applications., Durability & Strength: Features a tough nodular iron housing, stronger than standard OEM gray iron with additional 4 lbs of reinforcement, ensuring long-lasting performance., Precision Engineered: Meticulously assembled for optimal backlash, preload, and pinion shims, guaranteeing the correct pattern on ring gear teeth for reliable operation., Quiet & Efficient Operation: Clutch style positraction differential provides limited slip performance without the noise, making it ideal for smooth and quiet driving experiences., High-Quality Materials: Constructed with cold-rolled 8620 steel gears, large "Daytona" style pinion bearing support, and Vi Ford 9 Inch Posi Differential 3rd Member, 31 Spl, 3.70 Gear Ratio Sku # 91049345-31-370 Mfr. Part # 91049345-31-370 Condition New Brand Speedway Motors Sold Each Details Info As featured on Classic Truck’s Week to Wicked. Watch the transformation ! Assembled by Professionals Hand-assembled by trained experts in-house, our 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 Our 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. Stronger due to its larger bearings, our Daytona pinion support also uses the spacer-and-shim setup to maintain critical pinion depth settings under high load, unlike traditional crush sleeves which often compress further, take out your preload and lead to failure. With solid bearing spacers and the proper shims, we eliminate this problem and make setting preload easy and repeatable during installation, service and gear changes. Since preload is already set, simply torque the pinion nut to 160 ft./lbs. and you’re good to go. The pinion gear is connected to our new, forged steel “Ford short”, 1310-type pinion yoke. Note - Speedway Motors Differential 3rd members come with a 1310 Universal Joint (U-Joint) series yoke. No other Yoke size options are available. 1310 series U-Joint and Bearing Cap Reatainers Not Included - Clutch-Style Posi Differential with Proven Performance Our clutch-style posi differential gives you maximum traction. Based on the original limited-slip designs of the OEMs, these differential units provide the added benefits of experience over millions of miles and decades of proven reliability. A clutch-style operation means no clicking around corners and our posis feature heat-treated spider gears in a forged steel case. We’ve taken this posi to the next step in performance with increased clutch pressure and holding power, suiting it well for heavy-duty street car applications. has performed well in our Week to Wicked 1952 Chevy Truck, handling the job of transferring a 430 HP GM Performance LS3 to the ground. Clutch style, spider gear differential = proven reliability Spring-loaded clutch pack with improved grip over OEM designs Ideal for street tires and medium horsepower applications Housed in a Fully Machined, Reinforced Forged Steel Case Proven Reliability We run what we sell. Our third member units are the go-to choice for our own rides and we have built these units to last with high quality hardware and components. Tapered steel roller bearings minimize friction, better handle thrust loads and increase load carrying capacity. The ring gears are assembled with Grade 9 bolts with a tensile strength of 180,000 psi, a 15% increase over Grade 8 hardware. Heavy duty Grade 8 carrier cap bolts, a lock-style pinion nut with pre-applied Loctite and high-quality grade 5 pinion support bolts make our third member near-bulletproof. Units include a Viton® pinion seal providing long lasting oil and chemical resistance. This seal retains elasticity up to 399°F (204°C) and intermittently up to 600°F (316°C) This high temp seal helps eliminate pinion leaks, reduces maintenance and keeps the third member properly lubricated. A carrier-to-housing gasket is available separately. Our hand-assembled Ford 9 inch third member assemblies are made-to-order. We keep a supply of the most popular gears in stock, with most units built within 2-3 days. Our third-member units are shipped in a durable, reusable poly storage case, perfect for keeping multiple gear sets stored and ready for the track. Features Hand-assembled by our trained technicians for an unbeatable combination of quality and value Track-tested durability in our own cars – we race what we sell Precision assembly for the correct backlash, preload, and proper amount of pinion shims to ensure the correct pattern on the ring gear teeth Ring and pinion gears of 8620 cold-rolled steel for long wear Nodular iron housing is stronger than OEM “gray” iron and has 4 lbs of additional reinforcement Large “Daytona” style pinion bearing support for strength and reliability Spacer and shim setup maintains critical pinion depth settings and easier to service than traditional crush sleeves Clutch style positraction differential gives limited slip performance and quiet operation (no gears clicking!) Ring gears assembled with Grade 9 hardware, 15% stronger in tensile strength than Grade 8 Viton® pinion seal, resistant to chemicals and high temperatures Grade 8 Carrier cap bolts Lock-style pinion nut with pre-applied Loctite® Grade 5 pinion support bolts Includes form fitted, reusable red poly storage case Specs Differential Type:Limited Slip Housing Material:Cast-Iron Axle Splines:Select Spline/Ratio to see Gear Ratio:Select Spline/Ratio to see Yoke U-Joint Series:1310 Yoke Width:3-7/32" U-Joint Cap Size:1-1/16" Ring Gear Weight:Standard Weight:78.55 lbs MFG. Part #:Select Spline/Ratio to see Sold in Quantity:Each Gear Material:Steel Charts (PDF) Installation Tips Upon receipt and unboxing of your newly purchased 3rd member, prior to installation, it is recommended that the unit be prepped for installation by cleaning the surface of the unit with a form of cleaner such as aerosol brake cleaner and an air hose/compressed air. This is a normal step in your installation process, and this will properly and sufficiently remove any packaging remnants from the carry case / carry case hardware that may be found to adhered to the 3rd member surface upon receipt. 1310 series U-Joint and Bearing Cap Reatainers Not Included - Sold Seperatly 1310 Series U-Joint Measurments: Yoke Width 3-7/32" Cap Diameter 1.062" Recomended 1310 Universal Joint (U-Joint): Speedway 1310 Series Chevy to Chevy U-Joint - Part Number Dana Spicer 5-153X HD Greasable Cross U-Joint Chevy 1310 Series - Part Number Heavy Duty Greasable Cross U-Joint, 1310 and Driveshaft U-Bolts - Part Number Recomended U-Joint Bolts/Retainers: Universal Drive Shaft U-Bolts, 1-1/16 Inch Cap - Part Number Fast Shafts BBSK-10 Billet U-Bolt Strap Kit, 1-1/16 Inch - Part Number Moroso U-Joint Girdle - Part Number Specs Sold in Quantity Each Gear Material Steel Ring Gear Weight Standard Differential Type Limited Slip Spool Weight Standard Yoke U-Joint Series 1310 Weight 78.55 Axle Splines 31 Yoke Width 3-7/32" U-Joint Cap Size 1-1/16" Gear Ratio 3.70:1 Yoke Included Yes Housing Material Nodular Iron MFG. Part # 91049345-31-370 Ring and Pinion Included Yes Reviews Yes would buy again. Rated by Thunderhorse on February 24, 2022 Summary: will be a big improvement to my project ! Pros: very nice unit ! Yes, I recommend this product. a solid option for factory replacement Rated by Dillon on January 28, 2022 Summary: i took this to my mechanic to replace a 50 year old non posi third member and it was night and day, way more power afterwards. the pinion was too short for my 1971 Mach 1 mustang with a c4 trans so we had to install the old pinion but my mechanic seemed to have no issue with it. i have not driven it too much yet but if i have any problems i will update my review immediately. it had no noise whatsoever after installation. well worth the money. Yes, I recommend this product. Finally a 9" that does not whine Rated by Real MustangSteve on January 07, 2022 Summary: This rear end was installed in my 69 Mustang. 28 spline, 3.50 ratio traction lock. When I first opened the packing, which was broken in shipping, there was all kind of trash and broken red plastic on the gears. I noticed some cheap hardware store type flimsy washers under the ring gear attaching bolts. That is a definite no-no. Of, well. You get what you pay for. I have recently purchased a couple of 9" rears with the high dollar stuff in them for another car. Both came from Str**** Engin****** and both made noise, even after I paid $200 extra for "Stealth" gears that were guaranteed to be quiet. So I took a chance on the cheaper Speedway unit based on reviews that said it was quiet. The reviews were spot on. THIS THING MAKES ZERO NOISE. I wish I had known about these before I purchased all the high dollar stuff. I dont know about long term use with those lousy washers in it, but I will deal with that IF it causes a problem. I did not see any MADE IN USA marks on this Speedway rear end, so I assume it came from where everything else cheap comes from. But, if those folks can make a 9" Ford that doesnt whine, count me in. So far I am very happy with it. Only about 30 miles on it so far... Yes, I recommend this product. I will buy again Rated by Philip on October 12, 2021 Summary: installed in a 1948 Delivery truck Yes, I recommend this product. YES Rated by SUPER GENIUS on July 23, 2021 Summary: I LIKED NOT HAVING TO SET UP THE DIFF MYSELF AND SAVING MONEY ON IT ALSO. I COULD NOT HAVE PURCHASED ALL THOSE PARTS AND DONE IT MYSELF CHEAPER. Yes, I recommend this product. Related Items / Suggested Parts 9 Inch Ford Rearend Axle Housing 3rd Member Pumpkin Gasket Ford 9 Inch Clutch Posi Traction Third Member Install Kit Universal Steel Custom Length Driveshaft Kits, 3.5 Inch OD Tech Support We're here to help before and after your purchase. If you have a question or need assistance with one of our products, please contact us through eBay Messaging and a knowledgeable Speedway Motors team member will be happy to help. About Speedway Motors is America’s Oldest Speed Shop® and has been a trusted source for specialty rodding and racing products and friendly expert advice for more than 72 years. Founded in 1952 by “Speedy” Bill Smith – a racer and street rodder himself – Speedway has grown from a one-man operation to become the world’s largest manufacturer, distributor and retailer of street rod and racing products. Our industry-leading fast delivery is the result of same-day shipping from our state-of-the-art, centrally located 500,000 sq. ft. headquarters. Speedway’s size offers customers unmatched product selection and low pricing, while our excellent technical support and customer service have made us a recognized leader in the rodding and racing industries.

Price: 899.99 USD

Location: Lincoln, Nebraska

End Time: 2024-10-04T12:02:41.000Z

Shipping Cost: 0 USD