Question the 4x4 selector for this era of trucks.
 

I have an 08 z71, one of the options is automatic 4x4 mode. I like this option in the rain, and some days when their may be black ice in my area.

I'm looking to upgrade to a 2500 or 3500. I'm noticing they don't seem to have this mode. I thought maybe this was part of the z71 package, selected them only. Nope. :confused:

So, is this only a 1500 option? Can anyone tell me the rhyme or reason.. anything behind this option. I like it, but am really wanting to upgrade to a bigger engine and stronger suspension.