Another memorable “can’t be fixed” vehicle was a full-sized 2500 series Dodge Truck.
This vehicle had been sold new by a local dealership; it had a vibration problem. The service department tried several things to fix the vibration but could not. Under Utah’s vehicle “Lemon Law,” the dealership was about to have to repurchase a vehicle, and then I received a phone call from a former student of mine asking for help. This former student is now a technician at the Dodge dealership in this story.
While listening to the technician describe the history of this vehicle, I learned that in an attempt to repair the vibration, the dealership service department had replaced the following parts on the vehicle:
- Tires
- Wheels
They had also balanced the tires several times and balanced the driveshafts; nothing would fix this vibration. The vehicle must be a Lemon; it can’t be fixed.
Using the same diagnostic procedure outlined in our new NVH smartphone app, the technician and I performed a quick road test. While driving out of the parking lot to perform the road test, I could feel the entire truck shaking up and down. I told the technician that there has to be a tire or wheel that is out-of-round. He told me that they had swapped tire and wheel assemblies with another Dodge truck without vibration, but the vibration on this truck persisted. This eliminated the tires and wheels as the source of the vibration. I said, great; you have eliminated a lot of work for us. We proceeded with the road test.
As I suspected, the road test results indicated that the vehicle had a first-order tire speed-related vibration. As the NVH app’s diagnostic help file indicates, first-order tire speed-related vibrations can be caused by several problems on the vehicle.
- A tire or wheel with excessive runout
- A tire or wheel that is out-of-balance
- Stiff spots in the tire’s sidewalls (Force Variation)
- Wheel Stud Circle runout
- An axle flange that is out of round
- An axle hub center that is out of round
- A brake rotor or drum that is out-of-balance
- Drive axle problems
While the technician and I were working our way down this list of items to check, we discovered that the left front wheel stud circle runout was well beyond specifications for that vehicle. The wheel studs are part of the hub and bearing assembly.
Technicians at the Dodge dealership replaced the hub and bearing assembly with a new one, but it was worse than the original one. It took a third hub and bearing assembly to find one that was finally within specifications. Finally, the vehicle vibration was fixed.
There was a bad part on this vehicle. One very unhappy customer was the result. Hundreds of dollars were wasted on attempted repairs, many hours of labor were wasted because nobody knew how to diagnose a vibration problem; they were guessing! The NVH app eliminates the guesswork in vibration diagnosis and guides you step-by-step through the entire diagnostic and repair procedure.
What the app can do
The NVH app is designed to automatically detect the type of vibration your vehicle is experiencing, provided the instructions of the road test procedure are followed.
There are 14 types of vibrations the NVH app can automatically detect:
- Tire speed-related (1st, 2nd, and 3rd order vibrations)
- Driveshaft speed-related (1st, 2nd, and 3rd order vibrations)
- Engine speed-related (0.5, 1st, 2nd, 3rd, 4th, 5th, and 6th order vibrations)
- Electric Motor Speed Related (1st order vibrations)
Each type of vibration has unique causes. A vibration type is not the same thing as a vibration source. There are many possible causes (sources) for each vibration type. The NVH app includes step-by-step instructions on locating the vibration source once the app has identified the type of vibration.
What the app cannot do
- The NVH App cannot automatically tell you the source of a vibration
- Although the NVH app is excellent at identifying the type of vibration your vehicle is experiencing, you or someone else will need to follow the diagnostic steps described in the app help files to identify the exact cause or source of the vibration.
There are almost 300 possible sources of vibration concerns in today’s vehicles
THE NVH APP IS HERE!
Turn your Phone or Tablet into a Vibration diagnostic tool! Purchase our new App to use the internal sensors of your Phone or Tablet to diagnose the type of vibration your car or truck is experiencing. There are close to 300 individual vibration sources on a typical vehicle; the NVH App knows each one of them and can guide you through the entire diagnostic and repair procedures for each one of them.
