AZ: (4) Prime Chrome wheels and 2 unmounted tires
Let me see if I can explain this...
The track bar is responsible for keeping the axle from moving side to side, too much. In forward motion, the rear axle is going to stay straight because it's main attachment is behind 2 fixed leaf spring mounts.. on the frame. Up front, the axle is behind 2 non-stationary shackles. Sure they're bolted to the frame, but they're not fixed. The biggest difference you'll notice is a bit more roll when taking corners. Just slow down.
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