Does jeep need to be in four wheel drive all the time

SOURCE: jeep stuck in low four wheel drive

Put the transmission in neutral, emergency brake off, foot off the brake pedal, now try shifting out of 4 wheel drive low. If that doesn't work, drive forward, and again do the above, trans. in neutral, roll to a stop, foot off brake, try to disengage. What you're probably experiencing is called drive shaft 'wind up', and it is very difficult to disengage, but do the above and it should shift out of 4 low. countrycurt0

SOURCE: 4 wheel drive problem on Jeep YJ

you can also check the 4 wheel drive vacuum switch on top of the transfer case...got mine for 10 bucks from parts store...fixed the problem

SOURCE: 1999 jeep grand cherokee all time four wheel drive will not engage

Sounds like the splines on your transfer case gear are ground down

SOURCE: My jeep will drive normally

maybe the speed sensor on the transmission monitors transmission speed and sends info to computer to control shifting not sure if this is helpful

SOURCE: My 1995 Jeep Wrangler will

The transfer case needs to be checked. To check that the transfer case is engaged, then lift the Wrangler so all four wheels are off the ground. Engage 4wd (hi or low), start the Jeep and put it in drive. At least one front wheel and one back wheel should spin. Also check vacuum lines to the front axle and transfer case. If you have a bad check valve or a broken line, your transfer case can be in 4wd but your front axle wont engage.The Jeep Wranglers were equipped with a vacuum actuated Center Axle Disconnects (CAD). Its job is to engage the front axle when in 4x4 in engaged. These assembly's become very failure prone with age. They are easy to repair and replace, make sure to verify that it is receiving vacuum as the vacuum lines often go bad and leak. The CAD assembly is located on the back side of the front axle tube, just to the left of the pumpkin, when looking from the front.To see the vacuum line diagram,see the fig below:---
---------------------- If neither one of the front tires are driving while in 4x4, but the front driveshaft is spinning, you may have a front differential problem.------------- You must also try adjusting the screw holding the linkage. There is an adj screw on the back side of the linkage "bar" that you might need to adjust to get it to work right."Check the transfer case shifter to see if it will move to 4L. If not, the linkage will need adjusting. Place the shifter in 4L".To adjust you need to lift the lever. loosen the bolt, adjust the linkage where it seemed it needed to be, tighten the bolt, put it in 4H, 4L. Try this loosen bolt and pull lever to 4L and tighten, but if it wouldn't go back to 2H. Then put it in 2H and loosened bolt and pulled lever and tightened bolt. ---------------- This troubleshooting,procedure will help.Thanks.Helpmech.