I just changed the oil in my car (94 Z28) and noticed that the oil was really thin. I use Mobil 1 10w-30 on a regular basis. The oil seemed to have a really gassy smell to it. As far as I know the car is running in pretty good condition and the gas economy hasnt changed in the car whatsoever. I have talked to a couple of people about this and they told me that it is pretty normal with Mobil 1 to smell like gas when you drain it. Has anyone else noticed this? I think I am going to change to Valvevoline on my next oil change.