it's more likely a bit of both, but mostly the MJ wasn't selling well at the end. the XJ was selling like hotcakes and every MJ on that assembly line represented a loss of potential profit that an XJ in that spot would have provided. dwindling sales numbers, eating a profitable spot on the line, and the dakota already existed (and had an extended cab variant) all worked together to kill off the MJ. if it was purely the dakota, chrysler would likely have dropped the MJ in 1990 before spending money on the re-do. in their defense, they gave it a shot. it simply failed to sell. maybe we can call it the start of the end of the regular cab truck?