I basically want to know if this will help eliminate or reduce any possible negative effects on my joints from the impact on the treadmill and running.  I sometimes also go with a 20lbs vest for 20 mins at a time, at a 10 degree incline, and not running but definitely not walking either.  This is generally my warm up.  
Why not switch to something low impact like the elliptical since you already have joint issues?
I'd use the elliptical instead for now. I have a bad knee from a break and it took a few months of other work with a brace before I could handle jogging of any sort.