How do oil life monitors calculate oil life?

#1 (**permalink**) 03-17-2009, 02:34 AM

My Dad has a Chevy HHR. I recently drove it on a trip of about 1200 miles. He had the oil changed right before I left. By the end of the trip the computer said the oil life was at 94% still. So my question is 2 parts, 1) How does the computer calculate the oil change duration, and 2) what is the mileage interval or is it variable depending on conditions?

#2 (**permalink**) 03-17-2009, 02:34 AM

it just uses the odometer

#3 (**permalink**) 03-17-2009, 02:34 AM

it just uses the odometer