If there is one type of tire/wheel accident that every fleet fears the most, it has to be one that involves a loose wheel - or two. And when we say loose, we mean separated from the vehicle so it resembles a 200-pound unguided missile.
Since 1997, the Tire Industry Association (TIA) has trained and certified almost 50,000 technicians on the procedures they can follow to prevent wheel-off accidents. TIA has also partnered with companies like Alcoa and Michelin to produce educational videos that tire and transportation companies can use to reinforce the importance of following industry guidelines for installing all types of wheels and rims. Yet, despite all of these efforts, wheel-off accidents continue to occur, and people continue to suffer serious and fatal injuries as a result.
Recognizing how the impact of a loose truck tire and wheel assembly can destroy a car is the key to understanding how these accidents can be prevented. TIA released a free video called Wheel End Safety (available at www.tireindustry.org) so the industry can see firsthand what happens when a tire travelling at 55 mph strikes a stationary vehicle. The damage is compelling, and when you consider how it would be exponentially worse when a loose truck tire and wheel assembly strikes a vehicle travelling in the opposite direction, the consequences become very real.
So, TIA developed a list of five facts that every fleet must understand in order to prevent wheel-off accidents. A thorough understanding of these facts won't eliminate the chances simply because anything mechanical can fail even after the most thorough inspection and perfect installation. But TIA is positive that they are the keys to developing an effective wheel torque program that reduces the chances of a wheel-off and improves the performance.
1. Make sure that every technician who removes or installs wheels and rims from the vehicle is properly trained. Occupational Safety and Health Administration (OSHA) Regulation 29 CFR 1910.177 requires training for all employees that service truck tires and wheels. Since the OSHA definition of "service" includes removing and installing, even the mechanics that do not perform "tire work" must be trained if they handle the assemblies in any way.
If the technicians in the tire department are trained to follow the proper procedures, yet the mechanics do not follow those same procedures after brake, wheel end or suspension service, fleets should expect loose wheels.
2. Torque is not a magic potion. Pulpit-bangers that scream "torque, torque, torque" are usually the ones that are most interested in the collection plate. They want to scare fleets into buying the latest torque machine, and once they get the sale, they're never heard from again.
Yes, it is true that proper torque is extremely important. But it's equally true that there are a number of additional factors that will either prevent or contribute to loose wheels. Any supplier that tries to tell a fleet differently should be avoided like preachers that live in mansions and drive luxury cars while their flock struggles to make rent.
3. Impact wrenches are not torque control devices. The keys to all torque control devices are accuracy and repeatability.
Torque limiting adaptors (torque sticks) are considered by some to be precision instruments that can harness the raw power of impact wrenches so they deliver the proper amount of force every time. In order for the adaptor to work, the wrench should have 90 psi of running pressure, and the technician must know when to stop hammering so the repeatability is at best questionable while the accuracy is marginal.
Fleets love the feeling that they're doing something to prevent loose wheels and keeping the technicians happy. Until they lose a wheel and find out that TIA and the wheel companies do not recommend them for installing wheels or rims.