[jhv48]

Before you start replacing ball joints, have the fronts balanced while on the car. Might take a while to find a shop that can do it and it will take about 2-3 hours to complete both wheels.

But once done, if the shake still persists, it is not the wheels. Then look at the ball joints.

The shake you are experiencing seems to be characteristic of SPF for some reason. It took me about a year to finally rid my car of the 60-70 MPH willies. Now, it just shakes a bit if the tires are cold and have been sitting too long.

Balancing the entire front rotating assembly is the best solution right now.