Hello I am a newbie so bare with me.. Recently bought a 88 Fullsize blazer.. After getting home with it we noticed a severe poping noise while we were pulling a trailer.. Now it seems to do it whenever it feels fit to do so.. First we thought it may be the U-joints so we replaced them.. Then we thought the back brakes but they look fine.. It mainly does it when turning or going into a curve.. We then though oh no maybe the rearend.. So we had a mechanic friend drive it and he said it sounded like the rear end.. However what we dont understand is that it doesnt do it all the time.. Just whenever it wants to.. You guys think its in the rearend or something else? Also I want to mention that we noticed that the passenger side rear leaf spring has a broke leaf in it could this be causing the poping sound.. It sounds like it is coming from the rear.. Just dont know much about rearends and need a little help from the pros here.. Thanks guys!