65 MPH Front End Vibration

[Hooligan]

Originally Posted by rScotty

Balancing tires starts with checking that the wheel is symmetrical on the balance machine. Confirming hat the center hole is in the center, and that the rim is equidistant from the center. Every tire balance machine - whether cone, hub, or axle mount type - allows for this type measurement , but not every shop does it.

You might want to search for a shop that knows how to set up their balance machine and are willing to do so. Be aware it will cost more to do it right. That will double or triple the balance time and is not the sort of time that a shop gives away just to sell a set of tires. But worth it, IMHO.

Ask if you can watch the technician work. As the machine spins up you can see for yourself good balance jobspins smoothly without jumping.
rScotty

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This was a process over more than a week. Major chain tire shop. Wheel set up, centered, measured, spun and weighs applied. Spin to confirm and gave new results. Even replaced the centering cone from Hunter. 2nd shop had brand new equipment, still unable. Mercedes shop right on the money first time. Mounted to a hub.

[rScotty]

Different brnds of struts feature a spring and damping rate that is different from the factory equipment. In fact, those differences are exactly what the after market suspension company is selling you.

To answer your question - Yes, changing the spring and damping rate will change the amplitude and frequency of any unbalanced shaking that is going on. Tires and suspension are the classic case. Changing struts can even cause a quiet system to become a shaker.

All the after-market suspension companies make their living by betting that their engineering dept. does a better job on designing a smooth ride than the Mercedes engineers do. They back this up with advertising, and it's up to you to decide if their argument has merit.
This whole subject is simple basic mechanical engineering of vibration systems and is common throughout the manufacturing industry. It used to be as much art as science because the calculations were so complex and one brilliant designer could start his own custom spring and damper company. But anymore the design part it is just pushing buttons on a computer program. Now it is advertising as much as performance that sells after market suspensions.

rScotty