Probably not limited to the Durango , but my 2013 Durango with 5.7 and 40,000 miles has a slight clunk and in the middle of first gear. Usually starts to get noticeable after driving car for 10 minutes or more. Sometimes very noticeable , sometimes not so much. Even feel it sometimes when I just let the car idle off from a stop and hardly on the gas at all . Been going on for two to three years now and the dealer always tells me they cant find a problem. Dont know if its a tranny issue or something else. I almost think I felt it in reverse too.
Is there some type of lube they use on the driveshaft yolk that might have dried out ? Any ideas whats causing that ? Thanks.

 

This maybe?

https://dodgeforum.com/forum/3rd-gen...ation-fix.html

 

Yes I had my neighbors shop change the transfer case fluid and the problem went away.
Thanks