Try JCWHITNEY.COM they have manuals that might show them. It took me quite a while to finally figure out the vacuum diagram for the '87 Wrangler front axle system. If I can help, please contact me at ftretta@msn.com. My 91 Wrangler has same vacuum system and they are prone to problems. As long as your transfer case is shifting into 4WD (mine is), a better solution is a manual cable that replaces the funky vacumm motor on the front axel. It seems a bit pricy (around $200 if I remember correctly), but since I have already replaced the motor once several years ago, rather than spend the money to fix the now broken again funky set up, I think better money is on a cable to eliminate that weakness. I have seen several aftermarket suppliers carry it. Amazon or EBay might also be good sources.
The 2010 Jeep Wrangler has four wheel drive.
The 2008 Jeep Wrangler has four wheel drive.
The 2005 Jeep Wrangler has four wheel drive.
The 2011 Jeep Wrangler has four wheel drive.
The 2012 Jeep Wrangler has four wheel drive.
The 2014 Jeep Wrangler has four wheel drive.
The 2013 Jeep Wrangler has four wheel drive.
The 2006 Jeep Wrangler has four wheel drive.
The 2007 Jeep Wrangler has four wheel drive.
The 2002 Jeep Wrangler has four wheel drive.
The 2009 Jeep Wrangler has four wheel drive.
The 2004 Jeep Wrangler has four wheel drive.