Wow, I say you might have found your problem.I'd say compare it to really loud/ bad rod knock.... also almost feels like binding. Keep in mind I have had one of these old k10 or k5 trucks for the last 19 years... I also drove this truck days ago cycling through 4wd and turning. This is totally new... either I busted a ujoint somewhere up front or my tcase is out of adjustment or built wrong . Looking at the linkage for the other 241s and 208s I have my guess is I need to fine tune that.
View attachment 326488
I would have assumed the different lengths would be between the 241 and 208 but you have 3 different lengths.
Are they adjustable?

