I recently went to Colorado and was up on the mountain on some trails and had to switch to 4x4 low to pull a tree that had fallen out of the way of the trail. Was not a heavy tree so wasn't to harsh. But as I went to put the truck back in 2 wheel drive the truck said shift delayed and pull forward but then wouldn't go in gear at all or in 4 high. Needless to say it did this for 15 minutes and when I tried to put the truck in gear from neutral after it would act like it shifted it would just grind the gears. I got it bCk in gear finally and then had to put it in 4x4 one more time and it worked flawlessly. Then two days later had to do it again and the truck did the same thing but it sounded worse this time. Anybody know what this may be?