Bent Frame? 2011 Outlander Max 650 XT

I own a 2011 Ourlander Max 650 XT that I purchased new. Mainly use it for hunting, ice fishing, trail riding and plowing snow. Last year I noticed the left rear corner saging. I could pick up that corner with a little force and get rid of the sag. It would also make a creeping noise when I did this. I figured I blew out a shock. I recently replaced the rear shocks with the HPG stock kit. Unfortunately this did not fix the problem with the rear left corner saging. Has anyone on here had this problem? Any tip, pointer or advice on what to look at or replace would be greatly appreciated.