I am new to all of this, so I apoligize now for all the dumb questions. I was out in 4 High and came to a steep loose grade. I went to put the jeep into 4 low and it won't go. So i left it in 4 high and went along. I went to take it out of 4wd ( stopped in park) and some (minor) grinding and it shifted back into 2wd and went on my way. I went and put it back into 4h and nothing the shifter is loose and doesn't egage anything. What did i do? How can I fix it. I have a 99 TJ so the shift on the fly on the center console.