Knuckle Boom Trucks for Lifting and Transport Applications

[MikePhua]

Knuckle boom trucks offer compact lifting solutions with hydraulic articulation, making them ideal for urban logistics, generator installation, and marine engine handling. Choosing the right configuration depends on reach, payload, and control preferences.
Knuckle Boom Truck Overview
Knuckle boom trucks, also known as articulating crane trucks, combine a hydraulic crane with a flatbed or tractor chassis. Unlike traditional stiff-boom cranes, knuckle booms fold like a human finger, allowing compact storage and precise movement in tight spaces. Popular brands include Hiab, Palfinger, Fassi, and PM, with models ranging from light-duty 5-ton units to heavy-duty 80-ton configurations.
The concept originated in Europe, where narrow streets and dense urban environments demanded flexible lifting solutions. Hiab, founded in Sweden in 1944, pioneered the hydraulic knuckle boom and remains a market leader. Today, knuckle boom trucks are used globally in construction, utility, forestry, and marine sectors.
Terminology Note

• Hydraulic Extension: Telescoping boom sections powered by hydraulic cylinders.
  
• Jib: A secondary boom arm that increases reach and articulation.
  
• Outrigger Spread: The distance between stabilizing legs, affecting lift stability.
  
• Radio Remote: Wireless control system allowing the operator to stand clear during lifts.
  
• F.E.T.: Federal Excise Tax applied to new heavy trucks in the U.S., often avoided by purchasing used units.
  

Key Specifications for Heavy Lifting
Operators seeking a knuckle boom truck for generator sets and boat engines typically require:

• Minimum 40 feet of reach with a hook capacity of 4,100 lbs at full extension.
  
• Dual hydraulic functions to the tip, allowing rotation and winch control.
  
• Hydraulic extensions only, avoiding manual pull-outs for speed and safety.
  
• Outrigger spread of at least 21 feet for stability during side lifts.
  
• Optional jib for vertical reach and complex angles.
  
• Radio remote control for precision and operator safety.
  

These specs enable handling of heavy loads in confined spaces, such as marina docks or urban rooftops.
Used Equipment Market and Sourcing Tips

• Avoid older Hiab models with obsolete parts. Some units from the 1980s and 1990s have unsupported hydraulics and electronics.
  
• Consider Italian brands like Fassi or PM for modern features, but verify local service availability.
  
• Mounting on a heavy tractor chassis improves stability and payload capacity. Single-axle trucks may be underpowered for large cranes.
  
• Check for full hydraulic extension capability, as some budget models use manual pull-outs that slow operations.
  
• Inspect for wireless control compatibility, especially if retrofitting a crane onto an existing truck.
  

In British Columbia, a building supply company purchased a single-axle truck with a Hiab crane offering 40 feet of reach and wireless controls. However, the truck was too light for the crane, causing stability issues. This highlights the importance of matching crane size to chassis weight.
Regulatory and Operational Considerations

• F.E.T. avoidance is a major reason for buying used trucks. The tax can add 12% to the cost of a new unit.
  
• Crane certification may be required depending on jurisdiction. Operators should consider obtaining a crane ticket for legal compliance and safety.
  
• Load charts and stability calculations must be reviewed before each lift, especially when working near maximum reach.
  
• Routine maintenance includes hydraulic hose inspection, boom lubrication, and remote battery checks.
  

Conclusion
Knuckle boom trucks offer unmatched versatility for lifting tasks in tight or complex environments. With the right configuration—40-foot reach, 4,100 lb capacity, hydraulic extensions, and remote control—operators can handle generators, engines, and construction materials with speed and precision. Used units provide cost savings but require careful inspection and matching to the intended workload. As urban logistics and specialized lifting demands grow, the knuckle boom truck remains a vital tool in the modern fleet.