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How is oil life calculated and do I need to change it?

Outlaw

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My car has been in and out of shops for many months now and I've lost track of the time between my oil changes but not the miles. 2500 miles currently and I usually change at 2800-3k. Never had an oil message pop up and I reset it every oil change. Yesterday I picked my car and saw this message. Am I fine to wait the extra couple hundred miles which could take months at this rate (still needs to go back for more work). Or should I change it? I'm assuming the oil life goes down by time but I'm concerned the car might be measuring the oil itself and saying the oil is bad? First car I've had that has an oil life monitor

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allfivefifty

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Not to scare you; however, I suspect the algorithm uses RPM as part of the equation. Revving it higher (i.e., going to track days) will cause it to come up sooner versus highway driving and short shifting. Could it be that they took it for an Italian tune-up?
 
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glockholiday

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It's not actually "looking" at the oil. It's a calculation of time/load/RPMs etc. So the harder you run the car the faster it'll go down, also a lot of idling time makes it go down faster than cruising down the highway. For the record I never let my oil life monitor get lower than 30% and that was at 6000 miles of easy driving. I've also had it down to 40% with only 3000 miles on it while driving more aggressively.
 

NightmareMoon

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If they didnt reset that monitor at the last oil change, that would explain it
 

D Bergstrom

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I only put about 4,000 miles a year on my 2020, so I change the oil at one year after the last oil change. About the time one year comes up, I get the change oil soon message also. As others have said, it measures time and driving style, can’t test the oil itself to let you know it’s bad. I change at the one year mark regardless, I wouldn’t go much longer then that, but that is just me. I doubt going another few hundred miles in the next couple of months would hurt anything, but I know my mind wouldn’t let me do it! lol

Doug
 

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BreadBurner

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Not to scare you; however, I suspect the algorithm uses RPE as part of the equation. Revving it higher (i.e., going to track days) will cause it to come up sooner versus highway driving and short shifting. Could it be that they took it for an Italian tune-up?
RPE?
 
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Outlaw

Outlaw

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If you're letting the car sit a lot the timer still counts down. Your oil is just fine at 3k, it doesn't magically go bad after a year.
It's really only been sitting due to ongoing issues with shops. Once I have it in satisfactory condition it will go back to being my daily driver and the beater I have rn goes to the scrapyard. I just want my damn mustang back as my daily
 

Mark T-TB

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My Mach 1 is a weekend toy/cruiser kinda car (so far)...
And yet with the low usage - about 2300 miles for the spring '25 to spring '26 season - I was getting that same message for a couple of weeks in April this year before the oil change.
Here in the Philly / Delaware Valley area the spring temperatures are not always suitable for the Michelin summer tires...
10 quarts of synthetic oil in a car parked in a heated garage for the winter... seems like a "1-year" interval should be fine - but the computer doesn't know all of the details?
My conclusiton was that the computer is considering the time /calendar as the reason for the "alarm" 🤔
 

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Oakley

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i do it on the light even though i probably don't need to.
it costs more money but i know the engine is pristine inside.
no regrets.
 

Noleftist

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According to the Ford people I spoke with, the OLM is based on 0w-20 or 30 blended engine oil which is usually about 95 to 90% conventional oil.
Knowing this I know I am ahead with both better viscosity 5w-50 and full synthetic. I am not concerned about tracking and daily driving while running my OLM down to zero.
Cobra Jet post above, is also what I have learned.
I have also sent my fluids to labs for verification of my actions.
I also have the 2022 MACH 1 W/HP so I have better cooling than the mustangs without the extra heat exchanger for each fluid.
I Am also adding the 3 Race Louvers RT hood vents for better cooling of the engine and everything in the engine compartment And less lift/better downforce. Also I hope it stops the horrible hood flutter I get!
 
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Craig Brown

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That is why you have a dip stick! If you want to know your oils condition pull the dip stick and look at it. If the oil level is fine and the oil is still clean you are good. I change my oil and filter every 3500 miles. I don't care what Ford says about it. I never do the 5000 miles. My oil still looks clean when I do my oil change. It is just my maintenance schedule.
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