How is Oil Life determined?

Vanguard · Dec 3, 2015

I just purchased a certified 2013 EXL-RES last weekend and was told by the dealership that an oil change was done prior to delivery. When I checked the Oil Life on the dash, it reported 50%. I contacted the service manager and confirmed the work was done (work order showed it had been billed out). He suggested resetting it myself, or stopping by and they would reset it for me. I had assumed that the Oil Life indicator was based on a set mileage, so I took the opportunity to ask what the oil change interval is on the 2013 Ody (I changed my previous Ody every 5K kms.). He said that the vehicle monitors many different variables and that it would simply let me know when the oil requires changing...there is no specific mileage. He did say that 10K-12K kms is fairly typical, with conventional oil.

Does anyone know how the vehicle determines the Oil Life? 10-12K kms sounds like a lot on a conventional oil! How far would a synthetic go, and how would the vehicle know the difference?

1saxman · Dec 3, 2015

The OLM cannot know what oil you use. Obviously it has to be calibrated from the factory for the 'standard' oil recommended for the vehicle. If 0W-20 is the recommendation for your 2013, the default oil is Honda 0W-20 Synthetic Blend. If you use that, the OLM will be in sync as well as can be expected. If you opt for the Honda full-synthetic or a regular non-synthetic oil, the OLM will be meaningless except in the most general sense.
I go by the OLM as well as by what I see on the dipstick. I say this because your engine could have a problem and be using more fuel than it should. I don't think the OLM program can detect that and it would dilute your oil with fuel and make it get black quicker. So you have to keep your eyes open. You should check the oil every so often anyway. Unexpected leaks and other problems can happen.
So if you pull the dipstick and see clean oil, you can believe that the dealership for some unknown reason did not reset the OLM after changing the oil. You also need to know what they used in it so you know whether or not to go by the OLM.

pkrface · Dec 4, 2015

The OLM is a simple algorithm that tracks cold starts, time the engine spends running below normal operating temp. vs at normal operating temp., etc., and then estimates the oil lubricity remaining. It is calibrated to the factory oil fill, so no, it cannot tell if you choose to run full syn. My '06 and '07 both give me 8-9K miles between oil changes, which I ignore, and that is calibrated to regular dino oil. The reason I ignore it is my goal of 300K+ out of the van, so I do full syn every 5K, but if you tend to trade before 150K miles save your money and just follow the OLM.

Roy2001 · Dec 4, 2015

If the oil is clear, then they forgot to reset the maintenance light.

oldskewel · Dec 4, 2015

Roy2001 said:
If the oil is clear, then they forgot to reset the maintenance light.

Yes, for the immediate concern about whether they actually changed the oil, just pull the dipstick and see if the oil is clear or dirty.

I consider the magic maintenance indicator to be a marketing tactic to get you to stop thinking and just bring it in for maintenance when the light goes on. Everything in the preceding comments is correct as far as I know.

My BMW bases the maintenance light on fuel consumption rather than mileage, which makes sense. But all the other issues mentioned above apply there too.

1saxman · Dec 6, 2015

Actually we are talking about an OLM that shows you the percentage of oil life left. Unfortunately it cannot know whether you're using the cheap convenience store dino or the top shelf synthetic. Still, it's a useful guide - when it gets down to 10%, you should really take a hard look at it regardless of what quality the oil is.

davedrivesody · Dec 6, 2015

If you are uncertain about the condition of the oil near the end of its OLM life, say 10%, send a sample for analysis (e.g. Blackstone). They will supply an objective assessment which you can use in the future to change the oil using the OLM. I would never exceed the OLM, but the analysis could justify changing it sooner.

Always use the same oil and filter to maintain a stable relationship between OLM and oil life.

Dave

1saxman · Dec 7, 2015

By using a full-synthetic and having the oil analyzed, you could easily exceed the OLM without any problem. In the event of an engine warranty claim, you may have to prove what you did was okay but the oil analysis is part of that. My plan is to use the default oil and only change when the OLM is at 15% or lower, depending on how the oil looks. I get it done at the dealer so this will minimize oil change expenses

fishEH · Dec 7, 2015

I'm not used to these incredibly prolonged oil change intervals. Call me old school, whatever. Our '15 is at 5700 miles yet is still at 50% oil life. As soon as my order of filters comes in I'm changing it. I plan to change it at 10, 15, 20, 25k miles thereafter.
Cheap insurance, IMO.

How is Oil Life determined?

Vanguard

1saxman

pkrface

Roy2001

oldskewel

1saxman

davedrivesody

1saxman

fishEH

Top Contributors this Month

Recommended Communities