The abnormal growth is not a serious issue.  We sometimes see strange growth occur especially in areas where there is callus tissue developing around a wound but in some trees it is found in healthy bark.  The hole is not from an insect from what I have seen.  It goes along with the abnormal growth.  They can be pulled off the tree by hand or possibly by animals such as squirrels.  I would not remove them since it exposes internal tissue. It is not anything you can changes.  The sap leaking is from bacteria feeding internally on sap and it builds up internal pressure that forces the fluid out through a wound or damaged area.  This is called wetwood and there is not a way to control it and trees can live long lives with this going on inside the tree.  Make sure this tree is not exposed to other stresses that can weaken it such as drought.  

Ok thank you so much for the information :)