Thanks to all 3 of you. He does have many trains and since the wheels were moving i wondered if he could damage it. Now i know. and he will just watch it now!

Help me here, the neophyte. Just bought a new Bachmann set at Cosco (Cargo King). My grandson likes to manually push the train. I asked a local train guy (i know nothing about electric trains) and he said the wheels wont roll so no damage done if he slides it along the rails. But as you likely know the wheels do roll (at least some of them), so is it still true there is no damage? he moves it pretty carefully and without a lot of downward pressure.