We're near to completing 5 years on the road. We didn't have grandkids to leave, but we did have a major garage sale, put stuff in storage, sell the house, and head out.
I'm not sure you should try going completely full-time. Not sure what your housing situation is, but how about a 3-4 month trip? And then perhaps a longer one. And, as has been said, with all the technology available, it does change the issue of staying in touch.
We were at a resort park for the winter, and spent some time in the stained glass workshop. There was a lady there who had an iPad propped next to her workstation. She was viewing and chatting with her granddaughter! The granddaughter....wherever she physically was....was sitting at her work table working on some project, and the two just talked and chatted as they worked, as though they were in the same room. It was pretty cool. I even held up my work-in-process to get the girl's opinion of it.
So, there are options and creative ways to minimize the effect of going full-time.