If you use wire cable, keep it lubricated properly. If you think about it, flexing causes movement which causes heat and wear.
http://www.le-inc.com/productPages.jsp?productID=227
The 2001 Monolec works great on padlocks as well.
http://www.le-inc.com/productPages.jsp?productID=227
The 2001 Monolec works great on padlocks as well.