Greasing bearings question

We bought a 2017 travel trailer. I asked the mechanic that gave us the walk around about greasing the wheel bearings. He said if you want to grease them don't go crazy with the grease gun. One squirt every couple of years or you risk blowing the seal out. He did say it's better to pull them and repack the bearings. He told me to just pretty much ignore them for ten years. That they would not be a problem for a long time. My plan is to check to see that they are cool every now and again and ignore them otherwise. Maybe, in five years or so I'll give them a squirt of grease.