I have noticed this a few times and just chalked it up to driver error, sometimes while in 4wd high, and on back roads, it would pop back into 2wd. Today I noticed there is quite a bit of movement forward and back on the transfercase shifter when I pull out from a stop, or on/off/on throttle.

Is this a common worn out tranny mount? Im solo this week so I cant look and duplicate.

Thanks

 

It happened to my buddy's, 06. Very simple linkage adjustment. I think you just need to adjust it out a bit, so when in 4wd it stays in that detent.

 

What he said above. Mark with sharpie the present location of linkage clamp and then move the clamp 1/4" at a time. Mine had the same issue, I only had to move it the initial 1/4".