I had mine checked via spinning the tires on the car. The guy had to dig the unit out of his home stuff. we just spun them. this showed very little vibration on the car. but the car still was shaking bad...car body movement bad.
I totally agree with you, Fastd, on the cause of front end shaking/vibration. I also have read many threads and talked with many people about this subject. I do believe that each will have it's own cause. And it can be caused by any of the items I'm reviewing below.
What a mechanic by profession and a home car bulder friend told me to do was,
check and study everything in detail.
It can be like not seeing the tree because of the forest. So, this means, checking all nuts, bolts and fastners, checking all joints for looseness while loaded and unloaded, Rotate the steering wheel while tire are loaded and feel the joints for motion, wheel bearing, steering rack, Rack to steering wheel for tighness...rotational and axial movement, front alignment, shocks/strut (this may be my cause
), brake rotors (balance if you can & run out on mounting surface of wheel), wheel run out, tire balance and mounting...flapjack & cobrad seem to have the best insight here...while mounting the tires lube the tire and rim, seat at 40 PSI, I like this! The road force balance seems like the best approach. Don't over look anything! Did I miss anything?
Just an note on what confused me on my vibration issue. I had a mild steering wheel shake at 60 - 65 MPH, got the tires balanced, just a slight vibration at 65. However, at spin balancing noticed one tire was pretty out of round. So, decided to get new tires...the car after the new tires was 10X worse than before. almost not driveable at 55 - 65 mph. Now if the strut shock solves my problem, then the question is why did the old brand X tires (9k miles) not shake, while the new Y brand ones did? my view is...the tires had different springeness(sp)?
New parts are on the way...I'll update once replaced.