Another oil question.

[Millarduck]

As I write this, I'm at 93% Oil Life, changed my oil on 12/31/24 and have put 11 miles on it (the drive home). In less than a month and 11 miles later I lost 7% of oil life. Why?

I am convinced that the OLM reduces on time and not so much RPM and temps. I run Motorcraft full synthetic (dealer oil changes) and with less than 3000 miles/yr. I get down to 25% and change the oil. Synthetics should last a year in low mileage cars. Whether the oil is sitting in storage in a bottle or in storage in an engine, it should not degrade 7% every month.

I do believe in 1x year oil changes regardless of low mileage, but the OLM needs to "learn" when a car is not daily and actually monitor the oil, not the time. I change my daily every 5000-6000 miles. My daily (Jeep 4xe) is at 63% with the last oil change in June '24. If it was my Mustang I'd be under 20% with a quarter of the Jeep's mileage.

Sponsored

 

[Skye]

This why I always hate to seeing another oil topic discussed here!!!!
The outcome is always the same, bad!

I agree. I've currently got a few threads up on the specific topic of re-spinning or just starting. The replies are just as polarizing.

 

[FlipC]

My 2020 350R has an Automatic yearly oil change monitor. I changed it the first year, 21, but the next year I only drove it 1,000 miles so I didn't change it. Oil looked good so I just rest the yearly, milage oil rest. No Problems. Every 3k is when I change mine.

 

[robvas]

As I write this, I'm at 93% Oil Life, changed my oil on 12/31/24 and have put 11 miles on it (the drive home). In less than a month and 11 miles later I lost 7% of oil life. Why?

I am convinced that the OLM reduces on time and not so much RPM and temps. I run Motorcraft full synthetic (dealer oil changes) and with less than 3000 miles/yr. I get down to 25% and change the oil. Synthetics should last a year in low mileage cars. Whether the oil is sitting in storage in a bottle or in storage in an engine, it should not degrade 7% every month.

It is well known that the OLM uses time in its calculations

8% * 12 months = 96%

So a car that doesn't get driven, it will still drop to 0% in a year.

I think it's actually 8.3% but you get the idea

 

[Skye]

Some pages of this thread spoke to the interest of preparing and engine by building oil pressure before starting, such as when coming out of storage.

The weather has changed enough where I brought Skye out of hibernation today. Almost four months to the day of sitting. Not one RPM.

I meant to take interest in the time to start, watching the oil pressure before, during and after.

In the car and door closed, the fuel pump primed. I then went to start it, with nothing done beforehand. After spinning over for a little more than one second, the engine caught fire and immediately began building pressure. PSI climbed in a steady and strong fashion, ultimately pegging the needle as it does when cold. No ticks, rattles or odd noises. The engine did stay at a higher idle for a bit longer than usual. Otherwise, it was a nothing burger.

The first drive is simply a shakedown run. Went out for one hour straight. Other than a modest amount of flat-spotting in the first 15 minutes, everything was normal.

Some like to spin their engine beforehand, and that's cool. Each person is going to have their own sense if they'd like to do some kind of prep first. I do not. With these timeframes, on average four months, there is no indication anything detrimental is occuring. I do perform oil analysis. The results have never displayed a tell anything negative is taking place.

YMMV.

Sponsored