weird stuff

[CrazyJesster]

ok so saturday night about midnight my buddy calls me an hes stuck. in his 2000 z71 trying to get to someone else is stuck. so i get a phone call from him asking to come pull him out. sure no prob ill be there in a bit so i get there. put it in 4wd ive got a 2003 z71 and ive used the 4wd before testing it out. so i think im in 4hi im getting the chain hooked up usin the tow hook on the front. i go in reverse and he wont budge so i pull forward hit reverse again chain brakes. so we start all over next time chain an tow hook breaks. im not budgin him at all and my 4wd isnt working at all no front tire spinning. no error message saying service 4wd the 4hi lite is on. i finily get him out how i dont know heh. so i take it out of 4hi drive to a mudhole with water an soup in it. back down in it put it back in 4hi and it crawls right out no problem.

now before i got to where his truck was at i did have it in 4hi before i got in the spot he was stuck.

what could be the issue here with this not wanting to work at that time. the 2 other z71s ive had i have never had an issue one beein a 01 with the touch button. and one beein a 97 with a manual transfer case with a vortec 350 shoulda never got rid of it.