ORIGINAL: 86atrack4

Most likely your going to have to remove the tranny,mine was doing the same thing, and come to find the one way bearing was broke,and 2of 3 screws that hold the second gear to the OWB were coming out.Remove the tranny dissasemble and insp. then if everything is ok add some blue locktite to those 3 screws and set screw(not the shift adjustment set screw,the small one). Mine didn't even have any locktite on the screws , thats why the bearing took a crap.

Good luck!