I just got a 2008 Z71 Avalanche this is my first 4x4 it’s in decent shape inside and outside I got it cheap due to a collapsed lifter that I’ve fixed already but sounds like a prop airplane from the front end when driving over 45mph which I’m thinking maybe hub bearing also when I put it in 4x4 it makes a loud popping noise when accelerating I don’t hear any popping when turning unless I’m accelerating. Any ideas what the issue might be?

 

worn balljoints? Could be lots of things on a 17yo vehicle. have someone rock it while you inspect from underneath.