Shocks & struts

All for of my tires have cupping on the outside of them. I recently got a tire rotation, alignment and balance. Things have not improved. My ride just isn't the same from when I first bought the truck. After looking some things up on the internet it seems like my next option is to change my struts and shocks. I was looking to put Rancho RS5000 Shocks & Struts that will give my truck a 1.5" lift. The question I have is do I need to change my coils with these struts or will it okay if I use the ones that are currently on the truck? Thanks for your help