Is the oil life % indicator an automated thing where it just counts the miles driven or does it actually check the quality of the motor oil?

 

https://techinfo.honda.com/rjanisis/...707O00212A.pdf

"Based on the engine operating conditions and accumulated engine revolutions, the onboard computer in your vehicle calculates the remaining engine oil life and displays it as a percentage."

IME, changing the oil when the 15% notification pops up, can be at 8500 miles in my commuter (Honda Fit; 60 miles per day), vs 7000 miles for my wife's car (MDX; travels approximately 6 miles per day for work/kid-carpool).

 

^^^ what marmaladedad said. The car computes this data, it doesn't actually check the quality of the oil. The oil life indicator does a pretty good job, although if you're a bit hesitant to trust the ECU then you can stick to changing the oil at 5k-8k mile intervals (can maybe get away with 10k mile intervals) and keep track that way.

 

I'm at 240k miles and found intervals around 9,000 miles. Engine is perfect. Can't tell any difference from when it only had 9 miles.

 

I usually change mine after it hits 20%...which is almost always 8-9K miles.
The oil drained looks about the same as the new going in.

 

what about length of time between oil changes.
for example minder says 40%, but oil has not been change in over a year.
about 4k miles. not driven due to covid.

thanks

 

General rule of thumb for cars that aren't driven much is to change the oil once per year.

 

^
plus one

 

i am planning on changing oil after 1 year and 40% oil life.
but i wonder if pure synthetic oil degrade at low driven miles
even after 1 year.

thanks

 

Contamination is the concern. Vehicles that aren't driven as often usually contaminate the oil worse than vehicles used regularly. The water from condensation, fuel, and other contaminants from the sealants, bearings, etc go up over time.