Managers spend plenty of time tending to engines, fuel use, brakes and tire wear, as they should. However, too many times their technicians ignore suspensions, a major truck and trailer component that receives a fair share or wear and tear.
Wrong Parts Replacement
Many service technicians see more issues with people who don’t replace parts correctly. This includes re-torquing the fasteners correctly or cleaning the area before putting in the parts. Suspension manufacturers offer maintenance and replacement instructions on their website. Additionally, there are plenty of times where normal wear items are commonly overlooked. Nylon washers or beam spacers insulate hangers from trailing beams on most brands of air-ride suspensions. On steel-spring suspensions, there are wear pads between hangers and springs themselves. All of these wear out, and as a result a steel-on-steel situation comes about. If these items are not part of a regular maintenance schedule, it can lead to the more expensive replacement of the arms, springs and whatever else can be worn down.
Improper torquing of Fasteners
Improper torque is very common, on both trucks and trailers. Many times, technicians simply don’t do it as it sometimes is not on the preventative maintenance schedule. It’s important that this piece is written down.
Another common item that gets overlooked is not tightening various parts. When a part gets loose, it starts to wear out the flat surface between the fastener and component. Once it starts, there’s no stopping it, it will get worse. U-bolts that secure axles to suspensions are a common culprit. Many times they are found to not be secure. When a brand new truck is either driven or towed from the factory to a dealer or customer, the U-bolts are among the first things that “settle in” and they also “relax”. Because of this, checking the torque on U-bolts should be part of the pre-delivery inspection done by fleet technicians.
Movement in Places where it’s not Supposed to Occur
A mechanical suspensions moves and has a determined life span. Movement in the bolted areas, radius rod connectors, adjustments in the rods themselves and U-bolts, however, are not supposed to move. When they do, things wear out. It’s important for service personnel to retorque the fasteners out of habit.
These bolts aren’t easy to get to and some of the torque loads are quite high. It’s also, unfortunately, a dirty job. The nuts, depending on which way the bolts are put in, can be tricky as well depending on which way the bolts are put in. Rubber wears out and sometimes the vehicle has to be jacked up to take weight off the suspension to see correctly.
One of the most important and commonly neglected maintenance items is checking and re-aligning your axles. Axle alignment is something that should be done at least two times per year and periodic checks will lower your tire and fuel expense. Additionally, axles that are properly aligned, allow a driver to focus on driving instead of the steering wheel. This has huge safety implications along with employee satisfaction.
Stay current on not only your scheduled maintenance items, but continue to be vigilant in your preventative maintenance items. Your truck and its drivers will thank you.