Oil Change Frequency

The oil change computer only measures what it was programmed to measure . . . length of trips . . . miles driven . . . etc. How about start-up and shut-off driving? Maybe. How about short trip driving? Maybe. How about extended idle times? Maybe. My point is that any careful driver-owner can measure and evaluate what type of driving they have been doing and change accordingly. 3000 mile oil changes are a good starting point . . but just for example . . . last month our daughter (while learning to drive) drive our CIvic into an ice bank and split the seam on the bottom of the radiator. My wife drove it for two days and then told me “the temp was up on the Civic on my way home from work”. I changed the oil only 500 miles before that, but upon changing the radiator, coolant, thermostat and radiator cap I changed the oil again. How hot was it running? Only GOd and my wife know that . . . and neither is talking, but I felt better changing it because I thought it might have gotten “cooked”. Would the oil change computer have picked up on this? Doubt it. Rocketman

How many times does it need to be said that the GM OLM measures EVERYTHING. EVERYTHING. EVERY INPUT.

Short trips …long trips …all cold trips …towing …you name it …it reads it. All without some complex and expensive oil condition monitor to go bad.

It’s beautiful. Follow it and have an oil change interval custom just for you.

Measures everything UNTIL it fails…or a sensor goes bad. Lets see how well it’s working when the car has 250k miles on it.

Well, if it quits functioning, all a person has to do is change the oil on a regular basis–every 3000-5000 miles or 3 to 6 months. At 250,000 miles, it won’t make much difference as most of the useful life of the car has been used up anyway. The OLM is one feature on our Chevrolet Uplander that our Toyota 4Runner doesn’t have. I find it a convenient feature.

Problem is you may not know it’s failed…until it’s too late.

Triedag; your point EXACTLY! Those that don’t change oil often enough cannot get the car to anywhere near 250,000 miles because the engine won’t make it. By changing oil frequently enough, based on your driving pattern and climate, ensures that when the car expires you will still have not needed an engine overhaul, or a transmission rebuild, if you treat the transmission likewise.

One post refers to long oil changes as good for the environment. Where I live all used oil is recycled, and whatever makes the engine last as long as the rest of the car ensures its maximum life, and that’s really good for the environment.

What are you talking about? It’s SOFTWARE (firmware in reality). There’s nothing to go bad. If one of the OBDII sensors go bad JUST LIKE IT CAN ON ANY OBDII VEHICLE, you fix it anyway. If you’re negligent enough to drive around with a CEL light illuminated on your dash, you’re probably too incompetent to change your oil on time anyway.

Sorry, the OLM is one of GM’s crowning achievements and a great customer/consumer service in delivering value.

Ford has managed something nearly as good. It’s an hour meter that registers idle time. They even give you a mile factor of 33 miles per hour. So, between the odometer and the hour meter, you can figure your oil change interval. Not nearly as good as the GM OLM, but much better than a blind odometer where you have no idea how much fuel has gone through the engine.

Why do you think taxi service is considered severe? It’s not due to being hard on the engines. NOPE. It’s due to mileage being a poor measure of usage. If you tracked the fuel used, that would probably work well.

Two identical cars. One driving highway @ 25mpg. One driving urban all day getting 17 mpg. After 200 gallons of fuel, which one is due for a change? One has done 5000 miles and had two warm up cycles on the daily commute, and one has had traveled 3400 miles with one warm up cycle per day.

Now don’t confuse or swap that for truly “severe” service …which can be grandma going only to and from church in Frostbit Falls, ND where EVERY mile is a warm up mile.

No, I just lost the engine on my Mazda6, changing the oil every 3-5k, mfg suggests 7500. Only had 81k on the enginge.

Here is my personal opinion and experience. Around about 1980 I started changing oil every 5000 miles in every new or used car I owned. I looked around and saw that everyone who was recommending 3000 mile changes was selling oil, and everyone recommending 7500 mile changes was selling cars. I figured splitting the difference at 5000 was a nice round number and easy to remember. In that time I have owned 4 cars I bought new and the first 3 of those all went over 100,000 miles without burning oil or having any problems related to oil. The 4th one is an '06 Honda which has an oil life monitor and only has 48,000 miles on it so far.

With the Honda I’ve been following the oil life monitor and the first oil change it recommended came out to be around 5500 miles, the next one was about 8000 miles later, but I was doing longer trips in warm weather during that period. Now, in cold weather with shorter trips the percentage has dropped much more quickly. So, yes, the oil life monitors do take temperatures and usage pattern into account somehow. I’m going to trust it.

With used cars my experience has been varied, but if it didn’t burn oil when I got it, the 5000 mile interval didn’t seem to hurt. With cars that were obviously oil burners when I bought them, well what can I say, that ship had already sailed and all I could do was try to keep them topped up and changed. They usually didn’t get worse.

One point: I don’t think the oil change monitor senses the type of oil in the crankcase. In the interest of science, I put synthetic oil in the crankcase of my Uplander. The monitor called for a change just as it did for regular oil. The interval dramatically increases when I do over the road highway driving in the summer as opposed to short trips in the winter as it should do. In my cars without this oil change monitor, I did this anyway.

3000 miles conventional oil. 5000 synthetic. but this is only my opinion.

Oil change sensors also do not monitor atmospheric humidity, the amount of dust in the air, and engine performance; or not up to par performance for whatever reason or reasons.

I would add that my old Lincoln Mark and current Mark are identical (engine/oil/driving habits/oil change monitor) and the oil change feature would beep around 3500 miles on the old car compared to about 4500 miles on the current one. An electronic widget is always questionable until proven otherwise, and even then it’s not a slam dunk all of the time.

What are you talking about? It’s SOFTWARE (firmware in reality).

And what FEEDS that software it’s information to act upon?? Those things are called sensors…or some sort of input device. Software can’t DETECT anything on it’s own.

The difference between your older and newer Lincoln’s oil change monitor might just be a newer version of the software based on the experience of Ford after some years with more conservative programming. I mean, if I were designing this sort of thing I’d go conservative with some parameters early on, then tweak the program after doing oil testing on real world cars. I don’t know that’s what happened, just that as an engineer that’s how I’d approach it.

There are many variables to consider when desiding when to change your oils. Frequency is one, brand is important to some ane very important to others. Viscosity is important. The most important to me is the mechanic that chooses to drain the oil imediately and gives the oil enough time to drain through the block. I have given up on quicky changes done in and out in 10 minutes. If you check your oil frequently, you will notice your do it yourself (not rushed) oil change will show up clear/green in a weeks time rather than dirty/brown. This I have proven to myself more than once when I became lazy and paid to have someone do it for me. Even at the better shop it was rushed enough where I was sorry I wasted my money and time. You not only do a better job yourself but you do it cheaper and will discover other problems and potential problems. You will in the long run have a better and safer vehicle when you are “hands on” with the vehicle you drive. After all who has more at stake than yourself to see that things are done right. There is satifaction in doing your own repairs. I have had a great repair shop that I still use today change my engine oil in a new car just before a trip. A few hundred miles later at a stop light we smelled something burning. I checked the engine and found the oil cap wedged between the engine and the firewall. Could happen to anyone but I seem to have a better record doing me own work. P.S. I am not inclined to go 3000 miles except on the older 4 cyl engines. Our Dodge Dekota 6 cyl 4000-5000 miles
My cummins Dodge 7000-7500 miles seems to work ok. Thanks, charley 1952

Europe calling… Recommended oil change frequency seems to be much longer in Europe than in the US. I have a 2004 Renault Scenic - http://en.wikipedia.org/wiki/Renault_Scénic - and its service interval is 30,000 KM with no oil changes required in between. Oil is synthetic and I check it regularly and might have to top it up once or twice between services. Seems to stay pretty clean.

Unless you run off road…5000 is sufficient according most dealers, some of who try to get you to change as often as possible. Highway driving, high mileage, even 6500 sounds reasonable. We’ve got better things to do with our time when more often is unneeded. My tractor recommendation is 200 hrs. running at 2600 rpm.

It may be acceptable depending on the car to change the oil later. But that depends on the quality of the oil. Once you get past 3k the oil is not as resistant to heat. Even a perfectly tuned vehicle may start burning the oil as thermal protection and viscosity break down. At the very least Check the oil and make sure the color is good. I recommend changing at 3K

[b] What are you talking about? It’s SOFTWARE (firmware in reality).

And what FEEDS that software it’s information to act upon?? Those things are called sensors…or some sort of input device. Software can’t DETECT anything on it’s own.[/b]

Sure. What does your engine management system use, clairvoyance? …and again, would you drive around with a CEL lit perpetually?

…and for that matter, just what do you use to determine oil viability, some “scratch and sniff” method? Are your fingers and nose set up for hydrocarbon sensing? Is 3000 miles some “magic” number …passed down by pagan mystics from Stonehenge? 5000? 7500? …and is every service going to fatigue oil at the same rate in the same manner?

Nope. The thing is a true gem and far superior to anything that a human can duplicate without a testing lab riding around with them.

With a testing lab (used a couple of times) and having a somewhat fixed service profile (daily commute for years that’s not changed) you can probably manage it yourself by tracking fuel consumption. That accounts for loads, idling, etc.

Oil change sensors also do not monitor atmospheric humidity, the amount of dust in the air,

…and how do you do it, with your odometer? I haven’t seen the humidity indication or dust indication on mine yet. How does it show it?

and engine performance; or not up to par performance for whatever reason or reasons.

…but the PCM DOES read performance. It reads O2 levels …fuel trims …altitude (MAP) intake air temp …CFM (in MAF engines) …coolant temp …everything.

Now TRUE, the OLM can’t read dusty conditions …but the owners manual states JUST LIKE IT DOES IN EVERY NON-OLM CHASSIS - that you need to use a shorter OCI in those conditions.