I never said it DIC used your airfilter for estimating how much time you have left on your oil. I used that as an example of why an oil analysis report is nice to have done, because I probably would not have caught that until I cleaned my air filter. I own a DHP powertuner and I can purposely mess around with the oil life system by throwing off my tune. GM just used the oil monitoring system for normal dino oil and never designed it for synthetic. Lets not also forget oil technology has changed in the last 12 years since my GTP came off the showroom floor.