There can be several areas of slight backlash which can accumulate to make for an unacceptable amount of driveshaft rotation. One of the most common problems is wear on the pivot shaft where the spider gears rotate, or in the fit of the spider gear shaft in the carrier housing. Unfortunately, excessive backlash in the ring/pinion gear fit can also become a problem, and reducing that dimension by adjusting the tooth contact will almost always cause a gear whine and accelerated gear wear. Slop in the 2-speed system is almost always a parts replacement situation, as no adjustments are possible.
Jerry
