grinding noise

I own a RZR 800 since 2008, first edition. :). Anyway yesterday I noticed the front end makes a strange sound almost like a spring that is out of place, a clicking noise. I am not 100% sure is related with the 4×4 setting but when I stopped and moved the front wheels left and right I thought I heard something popping. It is intermittent but sounds nasty, like clicking. Any ideas of what it could be?
Thank you in advance for any opinions.
Al.