Is an "oil life indicator" a reliable indicator for when to change the oil?

General Motors has a similar system in my 2002 Silverado. The way I understand that it works is the computer looks at a variety of inputs to determine oil life. It looks at engine load, cold start cycles, engine rpms, conductivity of the oil and some others. I know in my case it works as advertised. In the summer the engine reaches operating temperature during my short daily commute and the change oil indicator light will come on at 3500 to 4000 miles, longer if I am doing some extended highway use during vacations. In the winter my vehicle will frequently not run long enough to reach normal operating temps for days at a time. In these situations the light will indicate an oil change is due in as little as 1500 miles. I am still cautious and change the oil at 5000 miles if the light hasn't come on. But that is my personal preference. Because of the fact that it doesn't come on at a regular interval I have to assume it works. The oil gets dirtier if I do a lot of very short stops and extra condensation builds up. The important thing is to use the type of oil the program is designed for. If the manufacturer specifies synthetic use synthetic. If you use something other than what is specified you won't get the benefits of the program.

The engine oil life indicator should be more than sufficient. Just make sure to check your dipstick every now and then to make sure you still have a good amount of oil. The indicator is alright, and I have trusted the one on my Avalanche so far with no problems.

Ive been a mechanic for 15 years and will tell you that you can go by the oil life indicator, but Ive always recomended changing oil every 3k miles. It never hurts to change the oil and in some cases if your engine does use a little oil then your more likely to not run it low. Of course always check the oil frequently. Also a good rule is always give your engine a little time to get the oil flowing and warm up especially in the winter months!

Changing oil every 3000 miles made sense in the mid 20th century. Car engines and oils have improved a lot since then.

Hondas built before just before oil monitor were added to dashboards had owner's manuals, and recommendations for engine oil changes every 10000 miles or at least once per year. This was based on not routinely driving through mountains, on dusty roads, in bumper to bumper traffic or pulling a trailer. Doing these things Honda called Severe Use, and recommended 5000 mile changes.

Based on 160,000 miles experience with Hondas of the same model,one new without the Maintenance Minder, the second one used with 80,000 miles on it. I say that the Oil Life Monitor is reliable. Follow it unless a dipstick test comes out gummy, milky or gritty or surprisingly low at a gas fill-up check.

Put your maintenance dollars into high quality synthetic oil and a top level filter rather than more frequently changing a cheaper conventional oil and filter (Jiffy Lube). Even if you have your Honda dealer do this,your wallet and engine will be happier.

btw, I've never had to add oil between my 10,000 mile/annual synthetic oil changes. It still looks amber at 5000 miles/6 months.

update: With my use changing to shorter trips and less frequent,once I passed 100,000 miles, the oil now gets sootier faster. It will be interesting to see if that changes after the 110,000 mile plug replacement and valve adjust.

NO! No, no, no, no, and no.

Yes this old long-haired hippy is gonna say some stuff that may not sit well with the Turbo Cognoscenti Elite, The Oil Mavens, and the OEM's that are looking at something called COO "cost of ownership".

But it might just register just fine with true tribologist gurus.

I will give you some opinions, and I faithfully allow you to evaluate what is fact.

1. Film strength is of the utmost importance. Especially on cold starts, extreme conditions, and high-sheer applications like racing.

2. Synthetic oils have longer chains that last longer and are much more "betterer". Also, pure synthetics under high degrading heat convert to molecules that are much less abrasive under high heat and don't impart the same stress to turbo bearing cartridges.

3. Any "oil" accumulates fine particles from the combustion process that can act as abrasives to an IC engine. It matters not one wit whether this is "Wolfbrains 10W-30" at $6.56 a gallon, or "Forumla One Extra Virgin Goat Synthetic" at $40 a quart. You operate your IC engine, bad stuff is made.

4. So who cares, except that all oil filters are NOT made alike. What Allied Signal (Fram) sells may not be the same as what a WIX or MAN filter provides. Not in pore size, not in bypass pressure, and certainly not what a nice Oberg filter screen will give you (provided you wash every 250 miles).

5. My point is that oil gets "dirty", and by dirty I mean filled with tiny abrasive particles that erode your IC engine. And this is NOT a function of the oil, this is a function of the engine and the filtration processes.

6. I have pulled oil from engines that have been in use for 20k miles. Filthy, sludgy, disgustingly dirty. Is this oil shot? Yes. And NO! It's still slippery oil, even of the dinosaur variety. The oil itself still lubricates. But what is totally detrimental is the amount of solvent chains (unburned hydrocarbons, hex rings) and carbon abrasive particles that are now part of this oil. And this phenomena exists no matter what lubricant you use, what ancient alien secret it came from, or how expensive it is, or what [purple] color it might be, or what top fuel dragster sponsors it. It's a fact of IC reciprocating combustion and piston rings and moon phase and a lot of stuff I will never understand. But it's still true.

7. SO... I will say to you, if you are willing to believe, that you best bet in your '93 Yugo OR your John Player Special Formula One car, is that you need FREQUENT oil changes. NOT because some oils last longer than others; just because you need to get the dirt (abrasive combustion products) out of the mix.

8. If you are rich, by all means use extra-virgin Goat synthetic. But I would still suggest changing at "frequent" intervals. Because the stuff gets dirty (abrasive) at the same rate based on a myriad of variables, NONE of which have to do with what kind of oil you use.

9. FILTER! filter, filter. You want extended oil changes? Buy the best possible filter you can afford. For street cars, a sub-micron Oberg screen makes little sense. The pore size guarantees ultimate filtration, at the expense of a complete tear-down and wash every other trip. On a $50k racing engine, this might be prudent. On a street car, this would be ludicrous.

10. So, I am suggesting that a proper "dino" API specification is just fine. For 3k-5k miles. If you want to run synthetic (or have a turbo) that's certainly "better", in a way, but that does not relieve you of any obligation to change the oil when it is dirty! And the "dirt stuff" accumulates at the same rate regardless of how the oil was made or how expensive it is.

So, that's just me: and old curmudgeon that insists that clean cheap oil in your engine is always better than dirty hyper-expensive oil, no matter your budget or engine technology...

Of course, your mil[e]age may very vary.

To answer the actual question [Pffft... Just now?] I think a 3K oil change interval is divine, with NO regard to what some computer suggests. No need to milk the Special Oil Goats in Moderno.

read the oil bible from SO HOW OFTEN SHOULD I CHANGE MY OIL? through MAINTENANCE MINDERS - WHEN THE CAR TELLS YOU WHEN TO CHANGE THE OIL

It is a good read and has lots of easy to understand concepts that make up modern oil change computer decisions.

Here are those sections quoted

SO HOW OFTEN SHOULD I CHANGE MY OIL?

You can never change your engine oil too frequently. The more you do it, the longer the engine will last. The whole debate about exactly when to change the oil is somewhat of a grey area. Manufacturers typically indicate every 10,000 miles or so. Your mate with a classic car says every 3,000 miles. Ole' Bob with the bad breath who drives a truck says he's never once changed the oil in his ve-hicle. Fact is, large quantities of water are produced by the normal combustion process and, depending on engine wear, some of it gets into the crank case. A good crank case breathing system ensures the water gets removed from there PDFQ, but even so, in cold weather a lot of condensation will take place. This is bad enough in itself, since water is not noted for its lubrication qualities in an engine, but even worse, that water dissolves any nitrates formed during the combustion process. If our memory of chemistry serves us right, that leaves a mixture of Nitric (HNO3) and Nitrous (HNO2) acid circulating round the engine! So not only does it suffer a high rate of wear at start-up and when the engine is cold, it suffers a high rate of subsequent corrosion during normal running or even when stationary.

The point we're trying to make is that the optimum time for changing oil ought to be related to a number of factors, of which distance travelled is probably one of the least important in most cases. Here is my selection in rough order of importance:

• Number of cold starts (more condensation in a cold engine)
• Ambient temperature (how long before warm enough to stop serious condensation)
• Effectiveness of crank case scavenging (more of that anon)
• State of wear of the engine (piston blow-by multiplies the problem)
• Accuracy of carburation during warm-up period (extra gook produced)
• Distance travelled (well, lets get that one out of the way)

If very clever (or obsessive) owner could probably come up with a really clever formula incorporating all those factors. However, we would give 1, 2, and 3 equal top weighting. Items 1 to 3 have to be taken together since a given number of "cold" starts in the Dakar in summer is not the same as an equal number conducted in Fargo in January. The effect in either case will be modified by how much gas gets past the pistons. What we are really after is the severity and duration of the initial condensation period. All other things being equal, that will indicate how much condensate will be produced and we would suggest that more than anything else determines when the oil should be dumped.

DAMMIT - GET TO THE POINT ALREADY!

Hang on a moment - if you really want the answer, there's a couple more factors that need to taken into account: Crank-case scavenging (that's the clever term for sucking the nasty fumes back out of the crank-case) - or lack of it - is a crucial multiplying factor affecting all the other items listed above. As an example, the worst we've heard of was a Ford Fiesta of the mid 70s or so. Its crank-case fume extraction was via a tiny orifice directly into the inlet manifold which obviously could not handle any significant volume of crank-case fumes without upsetting the carburation. The car in question had been used almost exclusively for 5 mile journeys to/from work, shopping etc, and it had always been serviced "by the book". Despite (or because of) this, the engine was totally buggered at 40,000 miles. Alternatively its possible to find a car that by virtue of excellent crank case fume scavenging could tolerate many more cold starts than one without. Taking all these into consideration, our philosophy would be to totally ignore the distance and change the oil twice a year - about November and March. Move these dates a bit according to the severity of the winter. An average family car will do around 14,000 miles per year and about 2/3 of that will fall in the March - November period. At the end of that period, the car will be getting close to the manufacturer-recommended oil change interval - but all that distance will have been done at reasonable temperatures, including long distance runs during vacations and good weather. During the November to March period it may accumulate only two or three thousand miles, all low temperature starts and mostly short runs.

Around 1995, an article in the ANWB journal (ANWB is the Dutch equivalent of the AA - or the AAA in the American case) reached more or less the same conclusion that distance was not very important. In their case they applied this to their road service fleet, which once started in the morning never got cold. In effect, they hardly ever changed the oil. It worked out at something like 30,000 miles between oil changes. They also had some kind of water or acid indicator attached to the end of the dipstick and went by that rather than distance.

THAT'S A POLITICIAN'S ANSWER - TALK ABOUT DODGING THE ENTIRE ISSUE!

Dodging the issue? We don't know how far a car is driven in a year, where it lives, the driving style of the owner, and many other things, so we can't tell what's right for any particular car. This author changed the oil and filter in his 1985 Audi Coupe every 5,000 miles. It had done over 150,000 miles when it was finally sold, wasn't leaking and didn't consume any oil. My Subarus got oil changes at 10,000 miles but were newer cars in a warmer environment. My VWs got oil changes at 8000 miles or so. If you must have a figure, then 8,000 is it.

MAINTENANCE MINDERS - WHEN THE CAR TELLS YOU WHEN TO CHANGE THE OIL

A lot of cars now come with maintenance minders - inbuilt systems designed to tell the driver when to change the oil rather than leaving it to guesswork. First generation systems were nothing more than mileage counters. When the car reached an interval of 3000 miles, the light came on. Now they're more involved. The system typically monitors driving style (in terms of how long is the throttle open for any given duration of driving), air intake and external temperatures, coolant temperatures and variations and engine timing (determined by load on the engine and octane of fuel). There's a clever formula that each manufacturer keeps to themselves that can take in any or all of these factors (and probably more) to determine how fast an average oil will be ageing in the engine. When it gets to the point where the system decides that time is up, a light will come on on the dash - typically "Maint Reqd" or "Service Reqd" (Note - this is NOT the "check engine" light). On some cars the various trip computer settings can be cycled through to see an oil life remaining readout - normally given as a percentage. This is a convenience function so the driver can tell at any point in time roughly how much longer to before an oil change. That's useful for planning road trips - don't go on a 2000km trip if the oil life remaining indicator shows 10%. On cars with these systems, I would defer to the onboard computer rather than trying to work it out for yourself. When the system tells you to change the oil, just do it. I've found that my 8,000 mile guesstimate above is pretty close to when the maintenance minder in my cars has indicated an oil change was due.

Don't rely on the maintenance minder. Some Hondas with the VCM (variable cylinder management) use oil. No blue smoke and no leaks, but the oil is used. 2 quarts in 3,000 miles. Almost fried the engine relying on the 10,000 mile dealer oil changes. Do your own research and see what I mean.....

I own a 2006 Honda Civic EX-L in galaxy grey metallic with a 5-speed automatic tranny. Purchased it new in March of 2006 and still have to this day. As of March 9th, 2019, I have 227,208 miles on him. Original engine, original transmission, NO dashboard warning lights, runs like the day I bought him. It has been serviced at Honda for everything, including oil changes. The dealership used 5w20 Pennzoil Conventional up until 2012. Now the dealership uses either 5w20 Pennzoil Synthetic Blend OR 0w20 Pennzoil Full Synthetic. $24.95+ tax and disposal for a 5w20 Synthetic Blend oil change is cheap. My maintenance minder in the car goes between 7,000-9,500 miles between changes, depending on my driving, but usually it’s at 15% life around 7,500 miles. Civic has never eaten a drop of oil and runs perfect. I’ve done ALL recommended maintenance including oil changes, brake pads/rotors, couple batteries, drain and fill all the fluids every 60k miles, valve cover gasket and seals, and two valve adjustments. Only items I’ve had to replace in 13 years and 227k miles were the A/C system, two rear wheel bearings, and an alternator. That’s it. So in my experience with using conventional oil and blends, it’s been completely fine. No problems. I just recommend that you stick with the same viscosity rating and weight of oil every change. Don’t use a 5w20 and then 10k miles later use a 5w30 and then 10k more use 0w20. Look in the manual for what’s correct for your region and use that. These are the engineers who built these cars. They know them the best. NOT the dealerships who try and press more maintenance than what’s really needed. I see it all the time. I’ve been in the auto industry for over 16 years. There are exceptions to that statement of course. Cheers!