Your tree appears to have some type of bacterial infection such as bacterial wetwood (slime flux) or some type of wood rot fungi.    Bacteria usually enters the tree from a cut or injury or from a pruning cut.  There is no cure for bacterial wetwood, but it will not kill your tree. Wood rot fungi will decompose dead wood found in the central trunk.

Bacterial Wetwood Or Slime Flux (psu.edu)

I didn't see an insect holes in your tree.  Sometimes boring insects can cause sap to seep from the tree and cause white streaks.

If you have split bark, decay and dying branches on your tree, it's probably time to cut down your tree, especially if it's near your house.  A certified arborist can assess the health of your tree and help you determine if you should remove it.  You can find a certified arborist in our area at TreesAreGood.org.

Thank you for contacting Ask Extension.