George Mandlazi, 32, would be back in court on Thursday for a formal bail application, police spokesperson Colonel Leonard Hlathi said.
The collision happened on 13 July, at a level crossing on the N4 between Malelane and Hectorspruit.
The truck was carrying farm workers.
Twenty-five people were killed and several others injured.
The train, carrying coal from Witbank to Maputo, dragged the truck for about 200m scattering bodies along the way.