Grand cherokee help!!!!!!!

Part-time means you can only use that setting on loose road surfaces like mud, dirt, snow, and gravel.

Part time is not to be used on pavement, even if it is wet. If you do this it will eventually damage the transfer case.

It is possible that there's a decal over the driver's sun visor. I realize that yours is a Grand Cherokee, but my XJ has such a decal which explains when to use the "Command Trac" 4WD.

jim