New to the site just days ago and can't believe how helpful everyone has been. I am new to the first series trucks and have many questions. I am trying to solve as many as possible by myself, but one eludes me. When installing a new trans cover/floor panel I noticed a small square headed plug on what I believe is the forward top of the torque tube, just behind where it connects to the 4 speed trans. This plug is opposite the speedo cable connection. I removed it and looked inside, and saw no fluids. I was wondering if one of you kind folks could please help me understand what this plug is for? Maybe it's a dumb question, but I don't want to screw things up by not asking. Thanks a million to whomever can assist me in this Mystery. Mannymoejack
