well after having the tranny shop rebuild my tranny three times (because of their faults) i go offroading and after a few hrs of it t case popped into 2wd. i go to put it back into 4wd and the shifter moves with no drag. the linkage popped off. so i put it back on. it works for a little while i go to shift into 2wd same thing. popped out. is there supposed to a clip or ring the holds linkages in or something worn that im just not seeing.