After the 2nd road force balancing, the ride is more normal than shaky. I've driven it for a few weeks now and it has not gotten worse.

It is hard to believe that it is that tricky to get a set of tires set and balanced correctly. I guess I've learned that you get what you pay for with tires...and the new ball joints didn't hurt either. It appears that the problem was the tires and ball joints.

One shop said they see folks having problems with the GYW in the second half of their useful life (my guess is that's common for any tire). The tread pattern has a little more spacing on that tire than the BFGs I put on this time. One suggestion to anyone reading this with a similar problem is to check other threads to research the best tires you should buy.

I wanted to close the loop on this issue so some other poor soul on a learning curve might benefit from my meanderings.

Thanks to all for your help.

 

I've had so much trouble with cheap tires over the 53 yrs I've been driving that I rarely buy anything but Michelins now. They have always run smoothly and quietly for the entire considerable life of the tread. I do get them periodically balanced whether they seem to need it or not.

Then again, Michelin owns BF Goodrich now the last I heard so I would think they are good too.

 

check your transmission tailshaft bushing. When it gets bad, the yoke can shift around and put the driveshaft out of balance/out of phase