Identifying the Swivel Housing on a Case 580 Super L 4WD

[MikePhua]

The Case 580 Super L and Its Axle Architecture
The Case 580 Super L backhoe loader, introduced in the mid-1990s, was part of Case Corporation’s L-series lineup, which emphasized improved operator comfort, hydraulic performance, and four-wheel-drive capability. The 580SL featured a Carraro-manufactured front axle assembly, known for its modular design and robust off-road performance. This axle includes a central differential housing, planetary hubs, and swivel housings that allow the wheels to articulate during steering while transmitting drive torque.
What Is a Swivel Housing and Why It Matters
The swivel housing, also called a steering knuckle or kingpin housing, is the cast component that connects the axle beam to the wheel hub. It allows the wheel to pivot for steering while supporting the vertical load and enclosing the CV joint or universal joint. In 4WD systems, it also houses the drive shaft that transmits torque to the hub. Identifying the correct swivel housing is essential when sourcing replacement parts, especially since multiple axle variants were used across the 580L, 580SL, and 580M models.
Locating the Casting Number or Part Identifier
On the Case 580 Super L, the swivel housing typically carries a cast-in part number or identifier. This number is not stamped but cast into the metal during manufacturing. It is usually located:

• On the outer face of the swivel housing, near the top kingpin cap
  
• Along the flat surface adjacent to the steering arm mount
  
• Behind accumulated grease or paint, requiring cleaning for visibility
  

Common part numbers for the 580SL swivel housing include 144456A1 and 397654A1, both of which are interchangeable in some axle configurations. These numbers are essential when ordering replacements, as slight differences in bearing seats or seal grooves can affect fitment.
Carraro Axle Variants and Compatibility
The 580SL used Carraro 26.16 and 26.18 axle assemblies depending on production year and configuration (standard vs. wide track). Each variant may have different swivel housing geometries. To confirm compatibility:

• Locate the axle serial number, typically stamped on the axle beam near the differential
  
• Cross-reference with Case parts catalogs or Carraro technical sheets
  
• Measure the kingpin bore diameter and bolt pattern if the casting number is illegible
  

In one documented case, a contractor mistakenly ordered a 580M swivel housing for a 580SL, only to find the steering arm mount offset by 5 mm, causing alignment issues.
Tips for Removal and Inspection
When removing the swivel housing:

• Support the axle securely and remove the wheel and hub assembly
  
• Disconnect the steering cylinder and tie rod
  
• Remove the kingpin caps and slide the housing off the axle beam
  
• Inspect the bearing races, seal surfaces, and CV joint splines for wear
  

If the housing is cracked or warped, replacement is recommended. Welding cast iron swivel housings is risky and often results in brittle repairs.
Conclusion
Identifying the correct swivel housing on a Case 580 Super L requires locating the cast-in part number, understanding axle variants, and verifying dimensions when necessary. With the right information, sourcing a compatible replacement becomes straightforward, ensuring safe and reliable operation of the 4WD system. As these machines age, accurate identification becomes even more critical, especially as aftermarket and OEM parts diverge in design tolerances.