I'm going to weigh in and say it might be a suspension issue. You stated that you replaced the front suspension. If I'm reading your initial post correctly you just replaced the front suspension with an identical one...no IFS. That stated I don't suppose you are utilizing a stabilizer bar up front. I had one of those crack on me. It made a "bang/pop" when it encountered movement...not always so it was hard to detect. I initially thought is was a broken ball joint...I at least could tell that the issue was in the front of the truck. Finally found it but like you it sure was/is a head scratcher. Let us know what the issue was.
