Buick/Olds: Tire Shake, buick park ave, wheel bearing

Question
2003 Buick Park Ave. Ultra. Purchased new 8/03 and have had a severe tire shake at speeds 62mph to 70mph since new. Tires were balanced several times at the dealer and they also sent out to independant tire shop for balancing but did not correct problem. Dealer changed tiresout from the original Eagles to Michelin. No help. Forced variation balance all 4 tires. Again no help. Detroit engineering then stated the problem was do to induced vibration and recommended changing the lower control arms and make sure fasteners are torqued to factory specs. This was done and again no improvement in the tire shake. Sure feels like out of balance but given the number of times tires have been balanced by both the dealer and outside agency probably will agree it is not the wheel balance. The car only has 2700 miles on it since we use our older car if going on a highway trip rather than fight the shake. Is there anything in your experience that could be causing this problem?

Answer
If it feels like it is comming from the frnt I would say you have a binding CV joint or one of the wheel bearing hubs were not machined properly or slightly bent. I have seen all of these happen.
You should give the dealer as much info as possible about when it happens and what makes it better or worse. Ex. Only happens above 60 but goes away at 70 mph. Feels like a sideways shake or an up and down vibration. Gets better or worse when turning to the left or the right.
Take it from me, these kind of vibrations are a technicians nightmare so please try and help with as much info as possible.
Thank you for asking and I hope they find and fix your problem, and if you could, drop me a line and let me know what they found.