Pull the lever that is just left of the shifter. If your vehicle is not going into 4WD then you should make sure all tires have the same tread depth and that your transfercase has fluid in it.
Rear wheel, and possibly four wheel drive.
Rear wheel drive with option of either four wheel drive or all wheel drive.
My Jeep Grand Cherokee Laredo 4.0L is all-time 4wd and its a 1998 model...
The 4 wheel drive switch is located on top of the transfer case
A Grand Cherokee is either rear wheel drive or four wheel/all wheel drive.
The 2014 Jeep Grand-Cherokee has rear wheel drive.
The 2004 Jeep Grand-Cherokee has rear wheel drive.
The 2009 Jeep Grand-Cherokee has rear wheel drive.
The 2013 Jeep Grand-Cherokee has rear wheel drive.
The 2008 Jeep Grand-Cherokee has rear wheel drive.
The 2006 Jeep Grand-Cherokee has rear wheel drive.
The 2003 Jeep Grand-Cherokee has rear wheel drive.