Been working on my jeep for a wile but haven't experienced any thing with the t-case yet. My jeep has recently started to have a hard time switching into 4hi from 2 and back. taking a look under it i saw this setup which seems to come from the shifter my question is what is this little screw and should it be tightened? it seems to be sticking out like 1/2" maybe more. also would the problem be coming from this area??? Thanks in advance

 

that's to adjust linkage. so you might pull that rusy linkage out and clean it. then adjust.

 

would adjusting it and cleaning it make it easier to switch between 2 and 4? Like i said this literally just started happening this week and ive never experienced anything with it before.

 

Same as above or wire brush it down a bit paint & lubricate it. Should do it