another question by me! I bought a 1987 jeep cherokee for a hunting truck it runs good just has a few little flaws. Anyways went hunting today got in the mudd and well i had to get pulled out after inspection of everything. When i lock the transfer case into 4Hi it wont do nothing it locks in cause i put the case in it and crawed under it and couldnt move the drive shaft going to the front end also u can hear the transfer case rotating so my question is. Is the 87 system ran off of vaccum lines. If so is there a diagram i can look at to see all the hoses so i can fix this problem or could it be something else thanks in advance guys for the help