I go with the DIC and the intervals seems to be 10k to 13k miles at 25%-30% left. using mobil 1 "extended performance!"

 

What parameters does the dic use to estimate oil life?

 

i'm not sure but I used blackstone and it confirmed what my DIC was saying, using several samples.

 

In general the engine computer uses miles, warm up cycles, and time. If you drive very little the DIC will ramp down mostly based on calendar time. If you drive lots of interstate miles in a short time the DIC will allow many more miles before nagging about the next oil change. The algorythm is actually very accurate.

 

so to the dic, the type of oil, regular or synthetic, mobil 1 or extended life doesn't matter since it doesn't account for it?

given what i know now, i think i'll follow the dic and consider using mobil 1 if not extended life like evois.

 

with all due respect, i never understood the value of sending oil samples to blackstone simply because they can't tell you causation like since you show x and y in your oil sample, engine tests have shown on your z vehicle that you're good to go for another t miles without any additional wear on internal components compared to fresh new oil.

wouldn't the geniuses at GM be the only ones who have access to such data that can begin to tell us anything meaningful? . maybe i'm just int he wrong business!

 

they actually tell you the wear items in the sample that is present. when it had the engine leak, the dealer added some dye and it showed in the sample that I sent them. plus it tells you the remaining base stocks of your oil.

 

but how does that tell you what's going on with the engine? an oil change is $80 at worst. it's supposed to get swapped out. an engine... quite a bit more of a pain in the rear. thx!