Speedway Ford 9 Inch Posi Rear End Assembly, 52 Inch Width

Looking for a budget-friendly, rock-solid foundation for your custom rear suspension? Look no further. Our fabricated steel Ford 9 inch axle housings feature all-new components for maximum durability. It’s an evolution of the rugged and reliable 9 inch Ford platform.

Designed with the Builder in Mind

This housing is pumpkin-centered with uniform-length axle tubes, side-to-side. So mounting suspension brackets, especially on triangulated 3-link and 4-link systems, is much easier. Unlike factory stamped housings, these fabricated plate-steel center sections provide a wide, flat surface for easy bracket attachment. Note that the pumpkin-centered design will offset the pinion yoke about 1" to the passenger side.

Axle tubes are 3” O.D. with a 3/16” wall thickness. Heavy-wall tubes, along with a larger center section, significantly reduce distortion during welding of rear-link brackets or spring pads. Billet steel “New Big Ford” (Torino) style bearing ends are fixture-welded (3.150” O.D. bearing, with 2.50” axle flange offset).

Improved Design for Greater Durability

In addition to the heavy-duty bearing ends, the axle tubes are supported with bracing inside the large center housing. This reduces flex in the rear end housing, which is something you won’t find on stamped factory 9 inch housings. Plus, gears stay well-lubed and run cooler thanks to a large-capacity fabricated center (holds more gear oil than stamped housings). Axle is vented on the driver’s side.

Yet, with improved durability, our fabricated axle housing is on average 2 pounds lighter than stock style housings of the same size! Add your choice of axle shafts and third member (sold separately), and you are ready to roll. Equip your race car, hot rod or 4X4 with Ford 9 inch parts from Speedway Motors to ensure there are no weak links in your driveline combination.

Total wheel-to-wheel mounting surface width is 52" (from hub-to-hub). The pumpkin is centered in the housing, which puts the pinion 1" offset from center, requiring different length axle shafts. For this 52" housing you will need one 26-5/8" long axle and one 24-1/4" long axle. This housing includes (8) T-bolts for the axle bearing retainer plates and (10) studs for the third member.

• Fabricated steel center section
• 3" O.D. axle tubes with 3/16" wall thickness
• Axle tubes are internally reinforced for additional strength, less flex
• Billet steel "New Big Ford" (Torino) style bearing ends
• Accepts brake kits for 2.50" axle shaft flange offset (from housing flange)
• Housing measures 47" from flange-to-flange
• Assembled rearend measures 52" from hub-to-hub (axle flange face-to-face)
• Centered pumpkin w/ 1" offset pinion yoke for easy suspension mock-up
• Greater-than-stock capacity center section holds more gear oil and runs cooler
• Requires different length axle shafts, left/right
• Includes vent on driver side axle tube
• Includes studs for 3rd member and 3/8” T-bolts for bearing retainer plates
• 3rd member sold separately

These steel axle shafts have a natural finish and are sold individually. They are perfect for small shops and will allow you to build your own custom width rear end easily. Axle length is measured from the flange to the end of the splines. Be sure to select your choice length; short or long, and either 28, 31 or 35 spline.

 

• Circle track / off road application 5/8" thread wheel studs sold separately 910-05957 and 910-05958
• Street application 1/2" thread wheel studs sold separately 910-05959 and 545-46190
• 9 Inch Ford
• 28, 31 or 35 spline axle
• Long or Short
  • 28/31 Spline Short axle is 29.5" length from face of axle flange to tip of the splines with 10 1/8" of spline length
  • 28/31 Spline Long axle is 33" length from face of axle flange to the tip of the splined end with 9-1/4" of spline
  • 35 Spline Short Axle is 29.5" length from face of axle flange to tip of the splines with 8" of spline length
  • 35 Spline Long Axle is 31.75"  length from face of axle flange to the tip of the splined end with 8" of spline
• Axle has the new style big bearing ends on it
• Bearing measures 3.150"
• Bearings already pressed in
• 2-1/2" Offset
• Drilled for 5 on 4-1/2", 5 on 4-3/4", and 5 on 5" wheel bolt patterns using 0.685" knurl dia.
• PA20 set bearing
• AR375 Torino retainer
• Axle length is from the flange to the end of the splines
• Axles sold each, not as a pair
• Axles have 3 bolt patterns in them: 5 on 4-1/2", 5 on 4-3/4", and 5 on 5"
• The hub pilot (center of the axle flange) measures 3.055"
• The O.D. of the axle flange measures 5.93"
• Hub Register O.D. is different on the 35 spline with 2.78"

For more information on determining the proper axle length and the Ford 9 Inch, be sure to check out our tech articles; How to Measure and ID Differential Housings and The Rearend Debate: Ford vs. Chevy.

Used to attach the 3rd member (pumpkin) to the rearend housing, works with Ford 8" and 9" rear axles.

Note: Includes aluminum washers

Our reusable rear differential gaskets have a steel core and non-stick coating. Fits 9" Ford rear axle third member housings.

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 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 - Sold Seperatly

Gear-Style Richmond Powertrax Grip Pro Differential  

For the ultimate in putting power to the pavement, Richmond Powertrax Grip Pro Traction Systems are the latest design in traction using 3 x 2 spiral gear technology. These differentials provide smooth, dependable operation combining a limited-slip differential with the strength of a fully machined, forged steel case. Because there are no friction plates, no friction modifier additive is necessary.  Always use a 80W-90 weight petroleum based gear oil with a GL-5 (or higher) rating, friction additive/modifiers should NOT BE USED.  Synthetic oils and oils containing friction modifiers are not recommended. 

Powertrax Grip Pro differentials are the ideal solution for just about any muscle car or truck on the road today. When you need that added traction so your muscle car puts power to the pavement instead of burning one wheel up, Powertrax Grip Pro limited slip differentials are your answer.

• Latest Posi-Trac Design
• Uses 3 x 2 Spiral Gear Technology
• Comes Fully Assembled
• Delivers Progressive & Variable Traction
• Allows You to Control How Much Traction is Applied
• Housed in a Fully Machined, 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 bearing “Daytona” style pinion bearing supports for strength and reliability
• Spacer and shim setup maintains critical pinion depth settings and easier to service than traditional crush sleeves
• Richmond Powertrax Grip Pro spiral gear differential gives positive traction without the noise of a full locker
• 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