11 hours ago
The challenge of balancing comfort and durability
When specifying a vocational truck for specialized work such as hauling heavy windows with a knuckleboom crane, suspension choice becomes critical. The operator needs a system that can handle steep, soft terrain while also protecting delicate cargo during long highway runs. This balance between off-road durability and on-road comfort often leads to the debate between air ride suspensions and walking beam or air-over-beam systems.
Terminology clarification
Retrofitting a truck with an AR2 system can be expensive, with kits priced around $7,000–$10,000 and installation pushing the total closer to $15,000. Availability is another concern, as some suspension models are discontinued if sales volumes drop. For operators with high budgets, investing in a newer truck already equipped with AR2 may be more practical than retrofitting.
Practical advice for specialized hauling
One operator recalled using a converted Mack garbage truck with camelback suspension to haul windows. While the truck was durable, the ride was so harsh that expensive glass often arrived with microfractures. Another contractor in Idaho installed an AR2 system on a septic pumper and reported that the smoother ride extended the life of both the truck and its mounted equipment. In contrast, a sod farm in Virginia opted for rough-terrain forklifts with flotation tires instead of modifying trucks, reducing lawn damage while still handling heavy loads.
Conclusion
The decision between air ride, walking beam, and air-over-beam suspensions depends on the balance between cargo protection, terrain requirements, and budget. For operators transporting fragile materials over long distances but still needing off-road capability, the AR2 hybrid system offers the best compromise. However, for those prioritizing simplicity and ruggedness, walking beam remains a proven choice, while air ride continues to dominate where comfort and cargo safety are paramount. This suspension debate reflects the broader challenge in vocational trucking: finding the right balance between toughness and finesse.
When specifying a vocational truck for specialized work such as hauling heavy windows with a knuckleboom crane, suspension choice becomes critical. The operator needs a system that can handle steep, soft terrain while also protecting delicate cargo during long highway runs. This balance between off-road durability and on-road comfort often leads to the debate between air ride suspensions and walking beam or air-over-beam systems.
Terminology clarification
- Walking Beam Suspension: A mechanical suspension using equalizing beams to distribute load between axles, known for durability and traction in rough terrain.
- Air Ride Suspension: A system that uses air bags to cushion the ride, offering superior comfort and reduced vibration but less suited to extreme off-road conditions.
- Air-Over-Beam (AR2): A hybrid system developed by Hendrickson that combines the equalizing strength of a beam suspension with the cushioning of air springs.
- CTIS (Central Tire Inflation System): A system that allows tire pressure adjustment from the cab, improving flotation on soft ground.
- Walking Beam
- Strengths: unmatched durability, excellent traction, proven in logging and mining.
- Weaknesses: harsh ride, high vibration transfer to cargo, less fuel-efficient on highways.
- Strengths: unmatched durability, excellent traction, proven in logging and mining.
- Air Ride
- Strengths: smooth ride, protects fragile loads, reduces driver fatigue, widely available.
- Weaknesses: less articulation on uneven ground, air bags vulnerable to puncture, not ideal for steep or muddy terrain.
- Strengths: smooth ride, protects fragile loads, reduces driver fatigue, widely available.
- Air-Over-Beam (AR2)
- Strengths: combines durability with improved ride quality, better suited for mixed-use applications.
- Weaknesses: higher cost, limited availability on second-hand trucks, retrofit kits can exceed $15,000 with labor.
Retrofitting a truck with an AR2 system can be expensive, with kits priced around $7,000–$10,000 and installation pushing the total closer to $15,000. Availability is another concern, as some suspension models are discontinued if sales volumes drop. For operators with high budgets, investing in a newer truck already equipped with AR2 may be more practical than retrofitting.
Practical advice for specialized hauling
- Cargo protection: For delicate loads like glass windows, air ride or air-over-beam is strongly recommended to minimize vibration damage.
- Terrain demands: If the truck must regularly traverse steep, muddy, or soft ground, walking beam or AR2 provides better traction and stability.
- Tire pressure management: Installing CTIS or using flotation tires can reduce ground damage and improve mobility on lawns or soft soil.
- Budget alignment: If the crane investment is $25,000–$60,000, allocating $15,000 for suspension upgrades may be justified to protect both cargo and equipment.
One operator recalled using a converted Mack garbage truck with camelback suspension to haul windows. While the truck was durable, the ride was so harsh that expensive glass often arrived with microfractures. Another contractor in Idaho installed an AR2 system on a septic pumper and reported that the smoother ride extended the life of both the truck and its mounted equipment. In contrast, a sod farm in Virginia opted for rough-terrain forklifts with flotation tires instead of modifying trucks, reducing lawn damage while still handling heavy loads.
Conclusion
The decision between air ride, walking beam, and air-over-beam suspensions depends on the balance between cargo protection, terrain requirements, and budget. For operators transporting fragile materials over long distances but still needing off-road capability, the AR2 hybrid system offers the best compromise. However, for those prioritizing simplicity and ruggedness, walking beam remains a proven choice, while air ride continues to dominate where comfort and cargo safety are paramount. This suspension debate reflects the broader challenge in vocational trucking: finding the right balance between toughness and finesse.
