I have a 2009 Silverado. 5.3 vortec. After my last oil change I checked the oil every 500 miles. I was burning, losing, using 1 quart per 500 miles. I've never noticed smoke. It doesn't leave marks on driveway. I topped it back off and have been driving in M5. First 500 miles when I checked, expecting to add a quart, it was right on level. Didn't have to add a drop. What's is the best programmer that won't break the bank? What's the benefit of using the programmer as opposed to driving in M5? I realize this is an old post but I thought I'd try anyway.