I read through the technique and I believe it is missing a few steps. During the flush procedure the helper should turn the wheel from lock to lock to flush all the fluid. At least this is true for rack systems -- I'm not sure if it's necessary for the worm screw type. If you turn the wheel from lock to lock, it is best done with the wheels off the ground to reduce the pressure of the fluid coming out.

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95 E320 Cabriolet, 169K