Product review (5 stars): Easy fix
You know you need to replace your cams when the refrigerator door does not close readily by itself when you release the door handle just before pushing it all the way shut.  This is the lower of the two cams.  I first replaced just the upper one.  You know, that really solved most of the problem:  the door then closed just like it should.  When replacing the upper cam, I noticed this lower cam was also worn.  I decided to purchase and install the lower one too.  It made a small difference.  Anyway, if you are trying save every penny then you might be able to solve your issue by just replacing the upper cam, but what the heck, do them both.  First be brave and lie down on the floor and give the cams a good inspection; swing the door a couple of times so you can see how these things work and if both look worn or just one.  In sum, my 11 year old refrigerator door snaps shut and I have no worries I will arrive home after a long workday only to encounter warm beer and spoiled milk on account of the door hanging slightly ajar.