Now, you want to be sure not to thread the rod end on the wrong way, because you need to maintain its purpose of being able to turn the metal rod that is the turnbuckle so that it will either extend or retract (lengthen or shorten) the rod while it's on the vehicle. In order to do so, one of your rod ends will screw on righty-tighty style, and the opposite end will thread on counter clockwise, or backwards. Pay special attention to how it threads on, because it'll make you seem really out of sorts, being a backwards thread. Both sides (ends) of the turnbuckle are meant to either screw on, making the turnbuckle shorter, or screw off, making the turnbuckle longer. You adjust with the turnbuckle installed on the vehicle, and one direction lengthens, opposite direction shortens.