From what I have read in previous threads, there is no actual life sensor. It is all based on driving habits which it total BS and makes the system useless in my opinion. I say this because I am hearing people who do alot of towing getting 6,000+ plus mile intervals as well as those who do not. I have not put any effort into confirming how the system works but will take the forum conversations for it. I just change mine every 3-4,000 miles and reset the "dumb@55" light when it does come on.

 

I have 50,000km on my truck now, and i find the oil light to be right on the mark! i have only used Castrol synthetic in my truck and i usually get 8000 - 9000km depending on my driving habbits. when i was using my trailer a lot this fall i got 7800km before the indicator came on. and now i just got 9400 before the indicator came on, and all i was doing was a lot of highway driving. so i put a lot of faith in the indicator

 

Well, I would not put any faith in it. I changed the oil 400 miles ago, used Castrol Semi-Synthetic till my 3rd oil change at which time I will go total synthetic like everything I own. To me....5-20 is a little to thin for a hard working engine, as Europeans are still using 5-40...I totally believe this is so we get better gas mileage, not for anything else. Are the tolerances that close, compared to european cars?? I find it hard to believe...6k between oil changes with 70-80 MPH, towing 8ooo#, idle t6ime, warm up time....to thin of an oil on my suggestion, common sense. Good Luck to the Dino oil people, Total IV synthetic or better for me.
3 years of mechanic school, and common sense.