When discussing suspensions, especially trailer suspensions, weight reduction is a big talking point. In the lighter weight dichotomy between fuel savings and increase payload potential, Russ Brazeal, PE, vice president of engineering for Hutchens Industries, manufacturer of mechanical trailer suspensions, sees both ends of the benefits.
“If you can save even 10 lbs. and keep that trailer for 15 years, just consider how much fuel you saved by not hauling that extra 10 lbs. around for thousands of miles” he says. “At the same time, you may be able to take advantage of that weight savings by hauling a little extra cargo. It’s a win-win any way you look at it.”
The other part of a trailer’s total cost of ownership (TCO) comes in maintenance costs over the life of the trailer. According to Brazeal, while air-ride suspensions have seen an increase in popularity in recent years, his company is now seeing a move back toward mechanical spring trailer suspensions. In addition to weight savings, the move is also driven by lower initial costs, less maintenance and the continued improvement in spring technology. Springs have always had a progressive rate to ride as soft as they can when the load is lighter and then provide higher roll stiffness as the load increases. When it comes to mechanical suspension maintenance, a spring suspension requires very little attention other than a commitment to keep the fasteners properly tightened.
“Springs absorb energy to protect the load. They can only absorb so many road inputs until they eventually reach the end of their fatigue life and you have to replace the springs,” he explains. “However, in many applications when the road conditions and payload are not abnormal, that never happens and the mechanical suspension and springs will outlast the life of the trailer. Even if there is a failure and the spring reaches the end of its life, many times a broken spring might not necessarily mean immediate downtime.”
