So I got an oil change as part of my 50k maintenance service, but looking at the service printout it stated something odd. Had me down for 6 qts. of oil when I only gave them 5 of my own (using Mobil 1 synth. extended life), of which they only used 4 and topped off the other 2 w/ Penzoil synth. extended life. Now not only do I have two different oils in my engine, though both synthetic and extended mileage, but the Penzoil was 5w-30 and my Mobil 1 was 10w-30! How much longer do I have w/ her before she's a gonner?!