I'm having trouble with something in my transmission or rear gear housing!! It will periodically slip and then act like the differential is trying to lock and unlock when the switch is in single wheel or diffirential lock position!' Has anyone else had this kinda trouble? I have it pulled out of my ranger now and it's at a shop being worked on but their telling me everything is up to oem specs and can't find anything internally wrong with it!! Any help please!! :? :? :?