Oil life monitor accuracy 2010 Duramax

[Maxman]

I have a 2010 GMC Sierra 2500HD 4x4 LMM Duramax. I run 15/40 Mobil full synthetic engine oil
50/50 city/hwy driving in California my monitor will tell me to change my oil at 2000 miles on my existing oil. Truck is completely stock with 146K miles and not driven hard.
All smog equipment intact
DPF recently professionally baked and cleaned with a clean bill of health
How accurate is it. Seems ridiculous to change the oil now and expensive

 

[Furious]

You should honestly never go by the oil life monitor on any vehicle they can be inaccurate. If you are worried about oil life send in a sample for analysis.

But my recommendation to you is pick a decent interval and write in a notebook or print out a service log each oil change when your next oil change is due. I personally do my own oil change stickers.

 

[twX]

The GM systems are mainly based on oil or coolant temperature, and total engine revolutions. In a warmer climate, and without an excessive amount of idling or stop and go driving, 2k miles really doesn't seem right. There's usually a time limit as well, typically 12 months. How long did it take you to put those miles on?

Could be you have a bad temperature sensor or thermostat stuck open, or the OLM might just be conservative for this engine, and tuned for cheap conventional oil. I'd go to 5k miles, then do a UOA.

 

[FreedomOne]

It's set for a year on age regardless of mileage. So if it's barely driven or not driven it counts down all the same.

 

[fantastic]

Sounds like 7500 miles easily for your interval.

 

[14Accent]

My '12 Regal's OLM seems to have a mind of it's own too, but with the opposite outcome: I was showing 68% remaining at 4k miles when I changed the oil a couple weeks ago, meaning I probably could have gone 10k according to the OLM. Not something I'd ever do on a turbo DI engine.