New aux lift axle suspension saves weight, has improved stabilizer design
Reyco Granning introduced a new auxiliary lift axle family — the LiftMaster — at the NTEA Work Truck Show last week. The axle family includes the ALAP-13 (PS) steerable and ALAP-13 (NS) non-steerable, and the new models are designed for the Class 7-8 market and are rated at a 13,200-lb. capacity.
According to Drake Sarault, the company's director of powered vehicles, the new models take the place of previous Reyco Granning models L132 (steerable) and L130 (non-steerable). "These new suspensions are an outcome of our continuous improvement process. We listen to customer feedback, analyze what our competitors are doing and challenge our engineers to create the best suspensions they know how."
One of the challenges facing Reyco Granning engineers was how to remove weight while maintaining strength and durability. "Fleets are always looking for ways to increase payload — and therefore revenue — but they don't want that at the expense of higher maintenance costs," stated John Hinz, chief engineer for powered vehicles.
According to Hinz, the company was able to remove 75 lbs. from the steerable version and approximately 100 lbs. from the non-steerable version, "and we did it while still passing our most stringent tests for vertical, lateral and longitudinal forces."
Customer feedback also played a role in the steering stabilizer design, the company notes. "Some self-steering auxiliary axles use a coil spring for stabilization," says Hinz, "but customers complain that the coils can become packed with mud or concrete and become inoperative. Some other designs use a horizontal shock damper, but the damper is under-sized and the fluid can cavitate and lose its effectiveness."
"Reyco Granning has solved the stabilizer issue with a large Bilstein gas-charged, monotube steer damper," Hinz continued. "This eliminates heat build-up and cavitation and maintains constant control of the steering mechanism."
Other standard features include an automatic lift function in reverse, eliminating the chance that a driver might forget to lift the axle manually. The LiftMaster series is covered by a 36-month, 300,000-mi. parts-only warranty, and a 12 month/100,000-mi. labor warranty for the main structural components including hangers, beams, clip plates, axle saddles, torque arms and bellow pads. Air spring lift axle suspension components such as valves, fasteners and bushings are covered by 12-month/100,000-mi. parts only and 6-month/12,000-mi. labor warranty.
