I can understand not trusting an email to tell you when to change your oil, but you really oughta try it. Validation engineers are notoriously conservative in making any claims that can come back to bite the company in warranty. When OnStar reads your vehicle system status, it's reading the same info that your Oil Life Sensor would read and reporting that back to you. That is a CONSERVATIVE estimate of oil life left.

This is a clearcut example of the old adage "your mileage may vary". Engine oil life is very much dependent on driving duty cycle. The chemical changes and viscosity changes are measurable. Two neighbors with the exact same vehicle but different driving patterns will get different OnStar reports on oil life.

If you are skeptical, you can always pop the hood and check the ol' dipstick for volume and clarity (just like in the olden days when televisions had knobs and radios had dials ). In the meantime, keep your money in your pocket and those oil cans on the shelf for the guy who REALLY needs to change theirs.

Peace,

Martin

I am NOT the official voice of GM with respect to Hybrid issues

I am NOT the official voice of GM with respect to Hybrid issues

I am NOT the official voice of GM with respect to Hybrid issues