When I have my wheel turned all the way to the left or right I hear a loud clicking noise that I can seem to diagnose. It's a 1998 GMC 1500, there are no CV boots as it is a RWD truck & only 2 wheel drive. It seems to happen more when it's cold, & it's not all the time. I'm stumped but it doesn't sound good.

check for worn front end parts, like ball joints, A frame bushings, and shock mounts that have broken or have cracked rubber bushings, as in this video https://www.youtube.com/watch?v=GDAFxt46PHk&t=55s