Is it best to stick with OEM plug wires or go aftermarket? I have read a few articles and now I am more confused than before I began. The Tahoe has 140k on the clock with the original wires. I replaced the plugs several years back with rapid fires. What is the interval of change on plugs in these modern engines? What about 02 sensors? Do they need to be replaced before failure? Any other tune up tips you can share I would appreciate it.