'99 silverado front end noise

[SlipknotLOG]

So it only makes this noise, kind of like a grinding sound, when its in 4wd. I replaced the left front CV shaft because the boot was ripped and the shaft was chewed up. I dont know if it matters but i replace the whole rear differential internals. Pinion bearings included. New transfer case, new U-joints front drive shaft and back, and some other sfuff but it still makes that noise. Front diff maybe?