I have an 07 2.5i SOHC with 89,000 miles on it. I changed the plugs and wires the other day and noticed the valve cover gaskets are leaking. I did some looking around here and its a repair I can do. However I started thinking, should I just take it in and have the timing belt and head gaskets replaced (which would include replacing valve cover gaskets)? I mean why wait until they starts leaking to replace them?