While driving my 2001 Cherokee in 4 high it continues to pop out of four high while driving it makes a grinding noise when it pops out I have red and watch many videos and forums on how to adjust the linkage I adjusted linkage a couple times just to b sure but still pops out while driving also it goes into 4x4 high and low very nicely but when driving down the road it pops out and makes grinding noise I have to pull over to get it in 2 wheel but then again it goes n 4x4 very nicely not sure what to do next

 

Check the key on the transfer case. Does it seem sloppy or crisp when manually moved into the 4wd position. Try tugging on the linkage and see if it pops out like that.

 

Check the transmission and motor mounts too. If they're bad, the transfer case can move side-side enough to cause linkage problems. The oem linkage isn't designed very well. If the bushings in the linkage are worn out, consider one of the aftermarket replacements that work much better. For example http://www.boostwerksengineering.com...-V20_p_25.html

 

First try soaking all the linkage with some spray penetrating oil.

 

What surface are you driving on? Mud, gravel, hard road?