The problem is as soon as a sprag does not drive the front axle, it is immediately thought and stated that the sprag is crap, never mind the operator does not know how a sprag works nor have read the TMs on the proper care/adjustrment, let alone do it, the amount of use our trucks get, a sprag should last quite a while, just adjusting the shift rod from the trans goes a long way for a proper working condition, draining/flushing instead of the oil being there forever getting gummer and gummer will also go a long for reliable operation, all well, I guess it is easier to change out a transfer case then it is to drain/flush the case or read the TMs.