Have you ever seen a truck going down the highway shaking so violently that the aerodynamic panels and the entire hood are shuddering? Most of this movement is due to an imbalance, but it’s important to understand the root of the problem.
Getting a vehicle to go down the road smoothly is a function of multiple factors, including but not limited to suspension systems, brake drum balance, centering of wheels and drums on the hub, worn or damaged steering components, engine and transmission mounts and centering of the tire on the wheel. If any of these factors are not perfect, the result may be felt in the driver’s seat or steering wheel.
Over the past 20 years, the problem seems to have gotten more complex. The majority of wheels in the class 8 market are hub-piloted, which sometimes leads to off-center installation – even if a tech follows the correct procedure. It was easier to center stud-piloted wheels because the wheel naturally had 10 inner nuts that kept the wheel center.
Keep in mind, it is possible to place a square tire on a tire balancing machine and work with it until it is perfectly balanced, but once the tire is mounted back on the truck and hits the ground the vehicle would not realistically be operable. My point is this – balancing the tire and wheel assembly is crucial, but it may only solve part of the problem.
How to Identify a Problem if Preventative Measures Fail
Following the TIA tire dismount and mount procedures and the TIA R.I.S.T. (remove debris, inspect components, snug in a star and torque to spec) procedures will help ensure that you get the tire centered on the rim, and the wheel centered on the hub.
So, if you experience a shaking in the steering wheel you likely have a problem in the front end, and if you can feel it in the seat it is likely in the rear. With an expanded focus to include an expert diagnoses of all factors that cause vibrations, you can once again go smoothly down the highway.
Make it a priority to get your truck inspected if an imbalance is suspected, and feel free to visit one of our TA-Petro locations where we can expose the root of the problem and get you back on the road.