[dtsimpala]

Hello Folks,

I changed my oil and oil filter for the first time ever today, and I haven't thrown a rod yet! I used that Castrol Edge Extended which says that you can get a whopping 20K miles with it. My question is, how will the oil life sensor know that the oil is good past the usual number?

Does it measure the properties of the oil and can determine that it isn't degrading? Or does it make assumptions about the oil and then run an algorithm taking into account the driving conditions?

I don't have a problem, I'm just curiuos.

 

[JimTech]

Hello Folks,

I changed my oil and oil filter for the first time ever today, and I haven't thrown a rod yet! I used that Castrol Edge Extended which says that you can get a whopping 20K miles with it. My question is, how will the oil life sensor know that the oil is good past the usual number?

Does it measure the properties of the oil and can determine that it isn't degrading? Or does it make assumptions about the oil and then run an algorithm taking into account the driving conditions?

I don't have a problem, I'm just curiuos.

It is an algorithm.

From GM literature;
"Based on data collected over decades of extensive powertrain testing, GM engineers have developed sophisticated algorithms that reflect how time, engine speeds, engine temperatures, load, and other factors affect oil life. By plugging in real-world data for those variables, the Oil Life Monitor can accurately calculate when an oil change is needed and display the remaining oil life within the Driver Information Center."

Regardless of the OLM indication, my owners manual says to change the oil at least once a year.

 

[Bill58]

My question is, how will the oil life sensor know that the oil is good past the usual number?

It won't know.

 

[1954 Chevy]

I wouldn't try to run a car for 20K miles without changing the oil, no matter what the oil manufacture claims. Proceed at your own risk, IMO.

 

[Brhatweed]

It's a miles/time based thing in the BCM, no real sensor.

 

[Colt Hero]

I wouldn’t be too impressed by “Oil Life Monitor”. GM initially blew up some engines when they had their fancy “algorithm” telling owners it was OK to change their oil every 10,000+ miles!

I mean ... who wrote this crazy algorithm, and how did it get past Quality Control?

Also - while this “sophisticated” algorithm was busy doing cartwheels and handstands inside the ECM, many engines seized up because it had no idea all the oil had either been consumed or leaked out!

So what good is this thing?

It’s only anecdotal at best.

Change your Full Synthetic oil every 5,000 miles (at most), and Conventional oil every 3500 miles (at most), and just remember to RESET the dumb OLM so it doesn’t pop up in between oil changes giving you false warnings!

 

[Brhatweed]

It all comes down to take care of your car and it will take care of you.

 

[VladThe]

I had originally assumed the oil life feature literally had sensors reading the quality of the oil. My own experience, and per all the totally on target comments above, I waaaay overestimated the current level of technology. When you reset the oil life to 100%, it assumes you just changed the oil...realistically you could have done nothing but reset the % and it has no way to know otherwise. You can put in old oil, the wrong oil, or whatever....and the sensor will only know if there is enough liquid in there and will have no idea if the oil is any good or not. The oil life % changes over time based primarily on the number of engine revolutions. So if you idle a lot, it takes down the oil life "faster" ... meaning you get fewer miles between changes. I am not sure if the algorithm takes into account the outside temperature, frequent rabbit starts, or any other more advanced factors beyond number of revs.

 

[P.C.]

Hello Folks,

I changed my oil and oil filter for the first time ever today, and I haven't thrown a rod yet! I used that Castrol Edge Extended which says that you can get a whopping 20K miles with it. My question is, how will the oil life sensor know that the oil is good past the usual number?

Does it measure the properties of the oil and can determine that it isn't degrading? Or does it make assumptions about the oil and then run an algorithm taking into account the driving conditions?

I don't have a problem, I'm just curiuos.

Pretty much based on engine revolutions. Some have what they call designed algorithms. Still, there are no sensors that can tell when the oil is past its service life. If that were the case, you wouldn't be able to reset the monitor without changing the oil.

 

[E-Man]

Pretty much based on engine revolutions. Some have what they call designed algorithms. Still, there are no sensors that can tell when the oil is past its service life. If that were the case, you wouldn't be able to reset the monitor without changing the oil.

When I had my 2011 Impala, I used to run conventional oil in it but the oil life was based mainly on miles driven and it assumed I was running synthetic because the one time I forgot to change it on time (3,500-4,000 miles) the 'Change Oil Now' message came up at about 5,500 miles.

 

[Jeepster09]

My boss went by "that sensor" to change his oil instead of using common sense and had to have camshaft replaced due to excessive wear on his Impala.