Re: 4 wheel not engaging
First things, first.
Get someone to look under Jeep to see if front driveshaft is turnig when you have it in 4wd, if the front driveshaft isn't turning then there's something wrong with the transfer case or the shi
9 times out of 10 if there is a problem with the front axle disconnects, it is a vacuum line problem and not the shift motor.
Start with the transfer case and work your way forward. To properly diagnose front axle vacuum disconnct problems easily, get yourself a hand vacuum pump, about $35, and a service manual. I cannot believe the number of people on this board who try to work on thier vehicles without a service manual. It is the single most important TOOL you can buy. The very first thing I buy when I get a new piece of machinery, whether it's a Jeep or a bike or a quad,or a lawn mower, or a weedwacker, is a service manual.
The factory manuals are the best, but a Chiltons or Haynes will work.
Personally, I maintain 30-40 internal combustion engines, and I have a service manual for every one of them!!!
Funny thing is, the more I practice, the luckier I get