My 34 foot class A RV was shaking so bad it shook out all the stuff in the cabinets. I towed it to a alignment place they could find anything wrong. They took it for a test drive up to 60 and nothing. Any ideas.
First and foremost I am at a disadvantage because I am unable to inspect your RV to see if I can locate the problem.
Listed below are some areas to look at that could be causing the problem you are experiencing:
*Missing Wheel Weights
*Damaged or Loose Drive Shaft
*Out of round tire/s
*Bad or broken shocks or springs
*Bad motor mounts
*Torque on transmission locking up causing Torgue Converter Chatter.
*If you notice the shaking or vibration only on braking; it could be warped brake discs or brake drums.
The fact that you have had your motorhome looked at and test driven and there was no vibration could eliminate everything that I have listed above.
There is one last possibly. If your motorhome is equipped with dual rear wheels there is a possibility that some road debris lodged between the dual tires causing the vibration and rattling you experienced and finally dislodged itself stopping the vibration.
These are my best "guesses" based on the limited information you have provided.
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