If you are lowered the usual suspect making the clunking noise is the single top hat nut under the rubber cover. They are not supposed to be reused (per Toyota manual) and have been known to come loose after lowering the car, especially if the keyway was not aligned when the top hat was put back on.
I'm not sure about the play in the shaft, but you can download all of the Toyota shop repair/wiring/tsb's from here. good luck
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