Choosing a career in commercial vehicle maintenance involves long hours, hard work, and the heavy burden that small errors can lead to monumental tragedies. We’re reminded of this every time a dash cam video captures a tractor-trailer’s wheel popping off the spindle at 70 mph and careening toward oncoming traffic. The driver immediately gets blamed, and for good reason, as they are required to perform the pre-trip inspections that should catch issues at the wheel-end that could create a wheel-off event.
However, these problems that drivers miss usually develop over time. And that means more than just one driver missed the issue. In the case of trailers, which are often shared among multiple drivers, a wheel-off can be the result of inadequate pre-trips by several drivers.
Fleets might not realize where the breakdown in the inspection process occurred, but rest assured, a fastidious plaintiff’s attorney will let them know during a civil suit. To land a nuclear verdict, they’ll pore over every document they can to prove negligence. Whatever the payout, the guilt of knowing your screw-up or inaction killed a family of four, for example, will still be the highest cost.
We previously went over how drivers can shore up inspections on their end, so let’s focus on what the shop and leadership can do.
Establish inspection and repair workflows
Anything improperly installed, replaced, or maintained on or near the wheel hinders a truck’s safe operation. This can be anything from a worn rotor that impedes braking to an underinflated tire more prone to blow out on the road.
For wheel-offs in particular, it often comes down to nuts and bolts. For example, if a lug nut is not tightened to the correct torque—either too little or too much—that can have ramifications later. For the unlucky driver who gets in the loose wheel’s way, that can mean death.
But it doesn’t have to be that way. Following the proper procedures will mitigate the potential for wheel-offs, as well as help the fleet and/or service provider in court should an incident occur.
Read more: Proactive approach to wheel-end health
First off, shop management should insist when it comes to wheel end maintenance that technicians take their time and do the job the right way as recommended by OEM and industry guidance, even if the fleet operations side (for in-house work) or customer (for third-party repairs) is demanding a truck. Or if it’s the day's last job. Or perhaps the bay is needed for something considered a higher priority.
“The long-term benefits of efficiency and safety far outweigh any immediate savings gained by neglect or cutting corners on standard maintenance cycles,” noted Todd DiMascio, senior director of global sales for Stemco.
And remember to show newer techs the correct steps, don’t just tell them. If it’s not feasible to teach every new tech the proper way to service wheel ends, you can always just grab a smartphone and point it at your best/most experienced tech the next time they do specific wheel-end jobs. Select video, press record, and you have an instant training video. Some shops with technical trainers may put a little higher production value and editing into these, but as long as you can see the area being repaired clearly and hear the tech, the new tech should know what your standards are.
Seth Murphee, truck service risk specialist at TravelCenters of America, noted technicians should employ the RIST method when servicing wheel ends:
- Remove debris from mating surfaces
- Inspect components
- Snug lug nuts in a star pattern
- Torque to manufacturer specification
“For example, you can torque the lug nuts to spec, but if there’s a peanut butter sandwich stuck between the wheels, eventually it’s going to work loose and create a gap,” Murphee explained. “Each step in RIST is equally important to ensure proper clamping force!”
Along with following manufacturer guidelines, DiMascio stressed the use of proper tools, including seal installation tools and torque wrenches. “Also, you should verify the bearing adjustment with a dial indicator,” he added.
There are also different inspection requirements when replacing parts.
“Wheel bolts should be inspected anytime the wheels are removed from the vehicle,” Maye said. “Use a thread pitch gauge or run a wheel nut the full length of the threads to check the bolts for possible stretch. Wheel bolt replacement is going to be based on vehicle application. Off-road operation will certainly be more likely to need replacement than general line haul and over-the-road operations.”
Tosie also stressed the need for regular supplier and OEM training to inspect specific wheel-end components: “Hands-on training is a great place to start, and then yearly online or virtual training for follow-up. Make sure the techs have easy access to the supplier’s literature and know how to use it.”
To simplify training and ensure quality and consistency across the fleet, Tosie suggested standardizing certain components, such as hubs.
Techs should also refer to drivers’ pre- and post-trip guidelines.
“During a PM inspection, we ask the technician to do everything we ask the driver to do in their pre-trip and post-trip inspections,” said Roger Maye, ConMet director of technical service. “We also ask the technician to inspect the magnetic fill plug in the barrel of the hub that comes standard on all ConMet drive and trailer axle hubs. The lubricant in steer hubs and hubs without magnetic fill plugs can be slightly more difficult to inspect, but must be done.”
This can be done by placing a magnet through the hubcap fill plug, and the tech should look for signs of metallic particles, which can indicate failing bearings, Maye said. He also advised to “look at the volume, color, and condition of the lubricant. Oil has a milky appearance when it has been contaminated by water. On trailer hubs lubricated with semi-fluid grease, we recommend removing the hubcap and inspecting the volume and the condition of the lubricant annually or every 100,000 miles, whichever comes first.”
And if there is ever a doubt about inspections or repairs, Maye encouraged technicians to contact the OE customer service line directly for help.
You can also check this video where Maye explains proper wheel-end lubrication techniques:
Additional wheel-end maintenance tips:
Refer to the repair history
Individual vehicle repair history can also help techs focus on potential problem areas. What maintenance was recently done at the wheel end? What has recently changed? If a tire gets changed out on the road by a roadside tech, the fleet should retorque fasteners within the next 100 road miles. If the fleet doesn’t have a way to track repair history and review recent DVIRs, conversations should be had as to how to integrate them.
Fleet maintenance software and electronic DVIRs may seem like a technological luxury for small fleets, but numerous providers can provide estimated ROI and work within a smaller fleet’s budget.
For example, an Atlanta carpet cleaning business with under 50 Chevy Express vans saved $3,500 in less than two months and cut vehicle inspection time by two-thirds with Fleetio’s eDVIR software, Fleet Maintenance previously reported.
Emphasize quality and continuous improvement
Back this up with quality checks by lead techs and/or supervisors. Again, follow specific OEM and industry guidelines. Supervisors should also have a mechanism in place to verify tools such as torque wrenches are calibrated correctly.
When a mistake is found, use it as a teachable moment. Some shops treat faulty repairs as comebacks and offer bonuses based on avoiding comebacks, as well as penalizing techs when comebacks are found.
“In some shops, that’ll keep you from getting your bonus, so even though you had 110% productivity, you won’t make your bonus, because you had a comeback,” noted DJ Painter, Technician as a Service lead at Noregon.
Read more: Improving repair accuracy by tracking comebacks
Ultimately, accidents on the road due to maintenance oversights should be seen as failures of leadership.
Fostering a shop culture that puts safety above all else is the low-hanging fruit of this particular troubleshooting tree. Supervisors, general managers, and executives should also examine how they can mitigate and eliminate wheel-offs whether they have experienced them in the past or not.
This means always having an eye on continuously improving shop processes.
A great example of this is Dan Flanagan, current VP of maintenance at CR England. While holding that role at Bulkmatic Transport in 2019, Flanagan sought to eliminate potential wheel-off events by implementing standards beyond the TMC recommendations. Drawing on his experience working on aircraft in the U.S. Marine Corps, he instituted a policy where a quality assurance representative (QAR) was present “to witness the critical process of the installation of the spindle nut and wheel lug nuts,” he explained.
This “certified observer” may include another technician in the shop, a dispatcher, or even a terminal manager with the proper training and credentials, Flanagan said. The job wouldn’t go on if a witness wasn’t available.
The new rule does take longer, so Bulkmatic adjusted the standard repair time to reflect the changes, a request made by the technicians.
Vendors who installed wheels at Bulkmatic sites would also have to follow these new standard operating procedures. Some vendors pushed back, Flanagan said at the time, but others appreciated the extra safety check.
Bulkmatic would also torque check each wheel lug nut during PM intervals, which was 60 days. After roadside maintenance involving wheel-end removal, the fleet also logged torque measurements in the maintenance system.
And to leave nothing to chance, Bulkmatic created weekly reports for its executives and shop managers to alert them when an asset was maintained by a third-party vendor more than once. The fleet would then bring that unit back for a PM by the internal maintenance team.
