So I went wheeling on Monday, and I've noticed that in 4 wheel drive only, when I depress the clutch while crawling, there is a sort of slapping sound. It only slaps 2 or 3 times but it happens every time I depress the clutch. I don't hear any any noise in 2wd. All control arms are brand new Johnny joints, should not be any axle wrap. Both diffs have brand new gears and carriers. The front end is an aussie locker, but it performs flawlessly. Ratchets nice and smooth on road, works great off road. I believe it's the front driveshaft slapping when load is taken off the trans; the front shaft has a little bit of play in it. I can spin the shaft just a little bit, the rear shaft has almost no play. The t case has an SYE kit with a brand new cv shaft. Any ideas what could be causing it or if it is even an issue?