I've had Silver Maples lose a limb due to snowload, and then have it drip sap and when I pruned off a good sized branch also. The sap suckers love my Norway maples as well, then I also have Alder growing on my property which they try to ring. I planted all the maples except a few native Big Leaf maples, in my early years of property ownership, I stuck with transplanting native shrubbery and trees as they were free.
Duane