5. CHECK YOUR BALL JOINTS:
There are two different types of movements you will see in your ball joints, the first is called RADIAL (shifting side to side) and the other is AXIAL (up and down). The amount of radial movement you see should not exceed 0.060" (1.5mm) and axial movement should not exceed 0.050" (1.25mm). Because it doesn't take a whole lot to be off, the best way to measure ball joint play is with a dial indicator. Here are steps you can use to check them:
1. From the axle, use a good floor jack to lift one of your tire off the ground. If you don't have a good floor jack, set your axle on a jack stand to hold it up securely in place.
2. From the side, place a long pry bar under the tire and have someone lift it up and down while you watch the lower ball joint for axial (up and down) movement. Any movement more than 0.050" is too much and would indicate that your ball joint is bad. Of course, if you can see this movement with your eyes, it's definitely bad.
3. Next, grab the tire at the 12 and 6 o'clock position and try to rock it back and forth while you have someone watch the upper joint for any movement. Any radial (side-to-side) movement more than 0.060" is too much. Again, if you can see the movement with your eyes and without any dial indicator, it's probably bad as well.
If they check out, I would check your unit bearings as well.