I tried to search for this but wasn't getting any good results. When i put my truck into reverse, and dont keep my hand on the shifter, it will pop out just enough so that im not going anwhere. Is this supposed to happen as a "safety feature"? Anyone have some info or a search term?

 

unless the shift lever is binding against body and pushing itself out, you will probablly find a internal trans problem. Bearing loose, gear teeth worn, internal linkage issue, ect.