Innovative suspension keeps lift-axle wheels on the ground while the truck backs up.
Lift axles, designed to help protect public streets from heavy trucks, don't prevent damage to truck frames during the 10% of time they spend on the jobsite. But Hendrickson Auxiliary Axle Systems recently introduced a steerable lift axle caster design. Until now, drivers had to lift their steerable lift axles before shifting into reverse. ParaRev's shifting mechanism is activated by a relay switch connected to the backup lights and pneumatically repositions the casters on both wheels from a fore to an aft position before the wheels turn.
The ParaRev axle has a rated capacity of 13,200 pounds and can be used in both pusher- and tag-axle applications. The axle provides a 13-inch lift. Installed, the complete assembly unit weighs 1,170 lbs. and provides a 25-degree wheel cut. The axle assembly is compact, measuring 27.9 inches from forward hanger edge to axle center, and it accommodates ABS brakes. ParaRev incorporates Hendrickson's Ultra axle design and is available on most truck manufacturers' chassis.
"We've been field-testing the ParaRev lift axle for the past year, and since June the system has been available for most Class 8 chassis arrangements," says Tim DeCesaro, a Hendrickson product engineer. "With their lift axles lowered, drivers said that they had more traction while backing in soft soil conditions, and less frame twisting," reports DeCesaro.
Keywords: lift axle, suspension, Hendrickson, steerable, ParaRev, frame twisting