I have a grafted silkleaf maple tree that is 4 years old and was doing great then we got hit with a blizzard that dropped 4 ft. of snow on top splitting all the main branches away from the tree but still attached. Tree is dormed and has dropped all folage for winter
Split Jap. Silkleaf Maple Tree From Blizzard
Certified GKH Gardening Expert
Bolting a split like that is the common solution for this.
This article, in the section on split forks, will have steps for using a bolt to repair the split:
But, that being said, it does not always work. You may want to bring in a tree specialist to look at it to help increase you chance of success.