Identifying Unknown Skid Steer Loaders: A Practical Guide to Model Recognition and Brand Tracing

[MikePhua]

Skid steer loaders are compact, versatile machines used across construction, landscaping, and agricultural industries. Their popularity stems from their ability to maneuver in tight spaces, operate a variety of attachments, and offer strong lifting power for their size. However, due to their modularity, wear over time, and the wide range of models and manufacturers—especially from the late 20th century—identifying a specific skid steer without clear markings or serial numbers can become a real puzzle.
This article explores the process of identifying an unknown skid steer loader, especially one without visible branding or ID plates. Drawing from practical experiences and field observations, we’ll examine strategies for recognition based on visual design elements, mechanical configurations, and parts compatibility—along with stories of successful (and failed) attempts at identification.
Challenges in Skid Steer Identification
Many older skid steer loaders lose their manufacturer decals, model stickers, and even VIN plates after years of use and repainting. Machines that pass through multiple owners or auction sites often lack documentation. When decals fade and data plates are removed, technicians and buyers are left to rely on visual clues and performance traits.
Common identification challenges include:

• Missing or unreadable serial/model number plates
  
• Repainted machines with non-original color schemes
  
• Interchangeable parts between brands and models
  
• Lack of records in older dealer systems
  
• Aftermarket modifications (custom cabs, added lights, or controls)
  

Key Clues for Identifying a Skid Steer Loader
To identify an unknown skid steer, begin with a detailed inspection of the machine's frame, components, and operating layout. Several distinguishing features can be used to narrow down the possibilities.

1. Boom Arm Design
   • Radial Lift: The boom arms pivot from a single hinge point, resulting in an arc-like lift path. Seen in older models like early Bobcat and New Holland machines.
     
   • Vertical Lift: The boom follows a more vertical path using additional linkages. This is common in newer models like the Bobcat S650 or CAT 262D.
     
2. Cab Shape and Entry Style
   • Some brands use side-entry (like JCB skid steers), while most use front-entry cabs.
     
   • The ROPS (Roll Over Protective Structure) shape varies. Case and Bobcat use different bar patterns and profiles.
     
3. Wheel and Axle Layout
   • Certain machines have fixed axles; others use chain drives internally.
     
   • Track width, bolt pattern, and hub design can also help identify the manufacturer.
     
4. Engine Location and Access
   • Some machines have rear-opening engine compartments (e.g., New Holland).
     
   • Air filter placement, radiator shroud design, and engine make (Kubota, Perkins, Deutz) are useful indicators.
     
5. Hydraulic and Control Systems
   • Joystick vs. lever-and-pedal control schemes suggest different generations and brands.
     
   • Foot pedal configurations can narrow down the manufacturer (e.g., Bobcat often uses twin pedals for lift/tilt).
     
6. Loader Arm Geometry and Lift Cylinder Placement
   • Brands like Gehl or Mustang often use visibly forward-leaning loader arms.
     
   • The placement of hydraulic cylinders—either on the boom or beneath the cab—can help distinguish models.
     

The Role of Casting Numbers and Part Codes
Even when serial numbers are gone, many components have casting numbers or part codes stamped into the metal. These may appear on:

• Hydraulic cylinders
  
• Loader arms
  
• Drive motors
  
• Engine covers
  
• Valve blocks
  

Searching for these codes in aftermarket part catalogs or calling dealers can yield clues. For instance, a part stamped “7002480” might be unique to a Bobcat 743 hydraulic valve.
Case Study: The Skid Steer with No Name
In one memorable example, a farmer in Wisconsin purchased a used skid steer at a farm auction. The machine was painted red with black arms, had no decals, and the only number found was "6055" painted on the boom. It had a four-cylinder diesel engine with a side-mounted radiator, foot pedals for control, and chain-driven wheels.
Initial guesses ranged from Bobcat to Thomas to Gehl. After comparing images, one mechanic noticed that the loader arms and cab closely matched the Gehl 4625 design, particularly the ROPS bar curve and the triangular boom pivot plates. The final confirmation came from the casting number on the hydraulic control valve, which matched a known Gehl part number.
With the model ID confirmed, the owner was able to order the correct filters and a replacement fan belt—which previously had been a guessing game.
The Mystery of Thomas Skid Steers
Another frequent source of confusion is Thomas Equipment, a Canadian manufacturer that produced numerous compact skid steers in the 1980s and 1990s. Many were rebadged for resale under different names (such as Mustang or Allis-Chalmers), often with little or no branding. The visual identifiers for Thomas machines include:

• Large, flat loader arms with external steel reinforcement plates
  
• Narrow cab entry width
  
• Simple, square bodywork
  
• Chain drive access through rear door only
  

A Thomas 133 or 153 model, especially after repainting, is notoriously difficult to identify without deep part matching.
Skid Steer Spotting by Paint Color and Wear Patterns
While unreliable alone, original paint schemes can aid identification:

• Bobcat: White with orange wheels
  
• Case: Yellow with black boom arms
  
• New Holland: Yellow body, black boom
  
• John Deere: Yellow with green or black highlights
  
• Mustang: Bright orange or yellow
  
• Thomas: Usually white or tan, often repainted
  

Where machines are heavily worn or repainted, look underneath at hard-to-reach areas like the inside of the cab or under the engine cover, where factory paint may remain.
Using Community Knowledge and Image Comparison
In the digital age, sharing photos online or comparing them against known model images can significantly speed up the process. Create a checklist comparing:

• Boom lift arc
  
• Cab structure
  
• Engine and exhaust layout
  
• Tire size and tread
  
• Control layout
  

Even if no one knows the exact model, someone with experience can often say, “That looks just like my old Case 1845C” or “That loader arm is definitely New Holland.”
Conclusion: Identification is a Forensic Process
Identifying an unknown skid steer is part mechanical detective work, part process of elimination. While it may seem trivial, correct identification allows for:

• Ordering proper replacement parts
  
• Understanding lift capacity and specifications
  
• Ensuring safety compliance with ROPS/FOPS standards
  
• Avoiding wrong fluid or filter types
  
• Enhancing resale value with a known model number
  

Ultimately, skid steer loaders—despite their rugged, simple appearance—contain numerous identifying traits embedded in their steel, design language, and componentry. With careful observation and a systematic approach, even the most mysterious machine can reveal its origins. Whether on a dusty farm or in a city jobsite, every loader has a story—and every clue brings you one step closer to solving it.