So last few days, I've had a plastic clicking sound while driving. It sounds just like if you have a tire rubbing on the body, but this is on flat and level ground so thats not it. I was thinking its either gotta be the tranny, or a differential. It sounds plasticy though and aren't all the gears in both tranny and diffs metal. Seems like the sound would be different, but IDK. I checked the spur gear to make sure I hadn't stripped it and its fine. I tried to do some tests while holding the truck off the ground but it stopped doing it as much, so I couldn't figure out if it was coming from the front rear or middle. Any ideas? I hate to tear the entire truck down looking for the problem.