A 4x4 truck. Are insurance implications my only concern? What defines a closed road and must it be posted as such? Is a snow covered road that isn't normally used considered closed? I guess I should call my insurance company, but any light you can shed would be appreciated. Basically, would you writ...

A friend of mine lives in a remote area, on a 3 season road. In winter, this road becomes a groomed snowmobile trail. Is it still legal for me to drive on it? It is not posted as closed as far as I know. Am I putting myself at risk of anything by driving on it?