I put a readlift 2.25 level on my truck a while back and have never had a problem. I didn't touch the IWEs or anything. Recently I was at my parent's place in NC and was driving through a field. I got up to a pretty steep hill on an angle (my front drivers side wheel was drooping and my rear passenger side was compressed) I put my truck in 4H and it started to clunk real bad in the front so I tried 4L and got the same issue. I went back to 2H and got onto a dirt road. There I used 4H and it was perfectly fine. All I can guess is the level and the angle of the hill were overextending my front driveline. Does this sound right? I thought with only a 2.25 level I wouldn't be having this issue. I thought the issue with a level was eventually wearing out my CVs and the UCAs

 

Even without the lift if the front is drooping that far you could have had issues. If I tell is working correctly in flat or slight incline/define I doubt you did any damage to any parts and that it was the angle.

 

Try this if you are still there. Put it in 4wd before you get to the hill and do the same approach and see if you have the same clunk. If not it was most likely the angle and the 4wd engaging. If you have the same clunk noise then have it checked out.

 

Sadly I'm no longer there, but I went ahead and ordered bilsteins for all 4 corners since the stock shocks were garbage. I'll swap the shocks out and remove the spacer and when I go back up on the 10th I'll try it again and post my results!