Trailer and body liftgates have done much to improve productivity and safety when loading and unloading truck cargo. However, as an electric-hydraulic system, liftgates require proper attention to keep them functioning well, especially because their location exposes them to the worst environmental and operational conditions. For some users, poor performance or flat-out stoppage of the liftgate from running the batteries flat is a growing concern that liftgate manufacturers are addressing with product improvements. Manufacturers are also emphasizing increased attention to routine maintenance to help keep a liftgate in trouble-free operation.
Industry solutions
Bill Rector, director of liftgate sales North America for SAF-Holland, explains that the liftgate industry is dealing with two primary issues: minimizing power consumption during liftgate operation, brought on by the anti-idling laws being enacted in states across the U.S.; and corrosion prevention, primarily due to the highly corrosive chemicals being used to pre-treat roads in snowy and icy areas.
To minimize power consumption and extend the useful life of batteries powering liftgate operations, manufacturers continue to improve liftgate designs to increase operating efficiency, minimize power consumption and improve battery recovery while recharging. Rector says to look for design features such as rollers with sealed roller bearings that will minimize friction during liftgate operation and result in less battery drain, which will result in more operating cycles per charge.
A properly designed charging system can significantly improve the battery recovery and battery life, especially in high-cycle operations. Properly sized cables and separate dedicated charging and grounding paths, also known as “dual-pole charging systems,” are examples of charging system improvements now in use.
Battery charging systems are becoming a widely chosen option, says Thomas Walker, president, Anthony Liftgates Inc. “They increase the charge rate by raising the voltage level to allow the amperage to charge the batteries more effectively.” They especially help on trucks that make frequent deliveries where standard power systems often do not provide enough voltage to allow adequate charging. The Trail Charger can automatically raise or lower the voltage output according to temperature changes to optimize the charge.
Bartt Suchland, marketing coordinator, Thieman Tailgates Inc., says liftgates now include: low-voltage thermal protection for motors; dual pumps and motors; and alternative charging methods.
The biggest liftgate issue is not properly assessing the usage profile upfront and consequently not being able to match this profile to the appropriate battery pack and recharging system, says Arnold Kowal, manager of technical support at Maxon Lift Corp. He warns the outcomes of this mismatch are low-voltage situations that damage the electrical components and can result in a stranded truck or trailer with a dysfunctional liftgate.
Peter J. Collins, vice-president, sales and marketing, Waltco Lift Corp., emphasizes installation to manufacturer guidelines, most importantly, proper grounding.
Corrosion control
Some manufacturers have added special treatments, such as SAF-Holland’s Black Armour, or hot-dip galvanized coatings, to provide a finish to resist the salt and chemicals used in snow and ice removal or the salt spray that gets blown onto equipment in coastal areas.
Maxon’s answer to corrosion problems on liftgates is called MaxPro–– “maximum protection paint.” Standard since January 2008, it’s a polymer-urea topcoat over an aluminum- based primer with high salt fog, magnesium chloride and impact/chip resistance. For more protection, MaxPro Z+ with a zinc-rich primer is optional.
Maintenance tips
Anthony’s Walker advocates a simple but thorough visual inspection of the liftgate mechanical hydraulic and electrical system at least once a week. The company offers short and simple inspection videos that show technicians the areas to inspect.
Thieman’s Suchland stresses following the liftgate owner’s manuals and maintenance guides. Keep the liftgates properly lubricated. Check that all electrical connections are clean and secure. Apply approved dielectric grease to all electrical connections to minimize corrosion. Also, check that charging systems are operating at peak performance and there are no leaks on cylinders, fittings or hoses.
Chuck Jeary, manager of technical sales and service for SAF-Holland, believes the most important preventative maintenance inspection is to perform a load test on the individual liftgate batteries and to check the liftgate charging system at the pump-box, at least quarterly.
Try to match recommended maintenance intervals to the vehicle’s PM schedule. High-cycle accounts should have more frequent maintenance intervals, Maxon’s Kowal says. Change the oil filter yearly or when system contamination is present; change hydraulic oil whenever contamination in the system is found.
Waltco’s Collins’ says to improve performance of liftgates, provide proper training to drivers on safe operation of the gate, daily inspection procedures and how to properly store the gate for travel. FE
