Whenever I do a low speed (under 25mph) hand-over-hand right turn, like at any street intersection the Disco makes a slight creaking sound. This doesn't happen from a full stop. I've kinda put this issue off as just an annoyance since the truck is showing its age, but should I be worried that it is something more serious?

 

Where does the creaking sound seem to be coming from?

If the suspension is compressing or the truck is leaning at all when you're hearing the sound you might just be hearing the springs move against the mounts. There are lots of other possibilities though...