I'll bet most Autoblog readers take pretty good care of their cars. And like me, I'll bet most of you change your oil about every 3,000 miles or so.But recently I got to wondering whether that's the right thing to do. After all, most automakers recommend far more extended intervals, usually around 7,500 miles. And with oil prices skyrocketing, I thought it might be a good idea to start following the owner's manual. But I wasn't really sure.
After all, over the years I've heard lots of different opinions on how often you should change your oil. Mechanics and oil companies say you should stick to the 3,000 mile interval, while automakers say most people don't need to change it that often. The synthetic oil people say you can even take it to 25,000 miles.
Obviously, they all have their own vested interest. If you're selling oil or oil changes, you want people changing their oil as frequently as possible. If you're selling cars, you'd like to see them wear out so people have to buy new ones. If you're selling synthetics you want to be able to charge a lot. So who should you believe? I decided I needed to hear first-hand from both sides, the auto industry and the oil industry.
John McElroy is host of the TV program "Autoline Detroit". Every week he brings his unique insights as an auto industry insider to Autoblog readers. Follow the jump to finish reading this week's editorial.
The oil guys tell me an oil change is an awfully cheap insurance policy for your engine. They admit that following the owner's manual is the proper thing to do, unless you do severe driving. But they have a pretty broad definition of what they consider "severe." Their definition includes driving in very cold or very hot weather, in dusty conditions, any fast acceleration, stop-and-go driving, long highway hauls, or doing any amount of towing. In other words, they think most people engage in severe driving.
The car guys, on the other hand, tell me that 3,000 mile intervals went out with hula-hoops. They say that made sense way back in the 1960's when carburetors let a lot of unburned gas get into the oil. But with fuel injection, much tighter engine tolerances, extremely strict emissions standards and with much better engine oil than was available 40 years ago, most of them have more than doubled that interval. And yet, they admit that interval varies with the type of engine in a car and how it's driven.
That's why a number of automakers use oil monitoring systems in their engines to tell the driver when to change the oil. These systems look at how many times the engine is started, how high it revs and how hot it runs. Some systems, like BMW's, actually measure the quality of the oil. Others, like GM's, use an algorithm to calculate when the oil needs changing. Thanks to this system GM says that most of its customers now change their oil at 8,500 miles instead of the recommended 7,500.
But it varies. A Chevrolet Trailblazer with the 4.2 liter I-6 is seeing oil change intervals of 12,000 to 13,000 miles, GM says. But the same vehicle with the 5.3 liter V8 typically needs an oil change at 7,000 miles. That's mainly because the I-6 has a big oil pan and takes 7 quarts of oil, versus 6 for the V8.
All this can have a huge impact on how much engine oil we use. Americans buy 1.1 billion gallons of engine oil a year. Using the automakers' suggested interval could put a big dent in that number. And yet, to put it in perspective, we burn about 420 million gallons of oil a day in the form of gasoline and diesel fuel. So our engine oil usage represents less than 3 days of fuel.
But it can have an enormous environmental impact. Even though most engine oil now gets recycled, the EPA says that 185 million gallons of it gets dumped on the ground, tossed in the trash, or poured down the drain. That translates into the equivalent of 17 Exxon Valdez oil spills every year.
But back to my dilemma. My car doesn't have an oil monitor so what should I do? Stick with what I've been doing and change the oil every 3,000 miles? Or do what the manual says and change it at 7,500? I think I'll compromise and bump it up to 5,000 miles-even though I can already hear my mechanic yelling about what an idiot I am.
###
Autoline Detroit
Airs every Sunday at 7:00AM on Speed and 10:30AM on Detroit Public Television.
Last Week's Show: "Add it Up"
Autoline Detroit Podcast
Click here to subscribe in iTunes
London 2008: Honda OSM concept roadster says, "Cheerio!"
London 2008: Lotus unveils the Evora
2010 Chevy Camaro - Official Details and Images
2010 Chevy Camaro - LIVE from the reveal
Volkswagen unveiling two-door Elise fighter in LA, new sports car
First Drive: Maserati Quattroporte S in Europe
First Drive: 2008 MINI Cooper S JCW
In the Autoblog Garage:2009 Nissan GT-R
North American Exclusive First Drive: Alfa MiTo
First Drive: 2009 Kia Borrego
Reader Comments (Page 1 of 2)
Hooper @ Mar 14th 2008 5:39PM
What about those of us who don't drive much? Can I go a year between oil changes?
Allan @ Mar 14th 2008 5:42PM
My owner's manual DOES say every 5000.
Level @ Mar 14th 2008 5:43PM
I agree 3000 miles is too early for oil changes these days with cars and oils being more advance these days, as stated compared to the 1960's
Personaly I use Mobil 1 synthetic oil with K&N filter and change it every 6000 miles...
UltraP @ Mar 14th 2008 5:49PM
I do my own oil changes. Toyota 1.8 DOHC engine; full synthetic every 10,000 miles. Zero problems.
Even after 10k the used synthetic oil has medium-amber color. Mineral oil turns black and thick after ~5k. For me the extra cost of the synthetic is worth it - fewer oil changes means less time under the car, it's better for the environment plus the lubrication properties are likely better with synthetic.
Playdrv4me @ Mar 14th 2008 5:50PM
3000 mile oil changes definitely are wasteful and part of the Jiffy Lube spin machine. I frequently see oil change nuts on automotive boards who even do it as often as every 1500 and insist they wouldn't have it any other way.
On cars that do not offer a reliable monitoring system I change the oil every six-thousand miles. On cars with with both synthetic oil requirements and monitoring systems I generally follow the manufacturers specification (on my M3, which uses an uber-expensive 10w-60 oil formulation by the way, it's as much as 15500 miles between changes, but will vary significantly when doing actual driving).
However, with either of these approaches I always maintain an eye on the appearance of the oil by checking it via dipstick every so often. Obviously, you should never let oil circulate more than 12 months regardless of what the OLM states. Time does alot more to oil than use does.
M @ Mar 15th 2008 1:22AM
BMW typically has around a 10-12K policy, but we've seen sludge problems in the dealership (I'm a BMW tech, but a fellow enthusiast 1st and foremost). I would recommend 7-8K with full synthetic on BMWs.
Going by appearances can be misleading. The additives in modern engine oils make them turn black far sooner than when they need to be changed (This is according to snippets I read by Mobil and Conoco-Phillips). Go by mileage and or your oil life monitor - not by how black the oil looks.
Playdrv4me @ Mar 15th 2008 2:32AM
That approach depends also on whether or not you have the factory maintenance program or the extended maintenance warranty. If the OLM is still showing 3 or 4k to the next oil change they'll be reluctant to do it. The better dealers will gladly do it around 1500 miles though, this M3 I just bought had about 900 to go and I didn't even have to ask.
As far as the way oil looks, it should never be black or sludgy regardless of what kind of oil it is. I had a 2004 325Ci that was poorly maintained had gone 10k OVER the Oil Service indication and the oil was still dark brown at that point.
If the oil on any of my cars rubbed off black I'd be concerned.
Colin Smith @ Mar 14th 2008 5:51PM
My car goes in for a service once a year, whether it needs it or not, and has its oil changed then!
In Europe no modern cars require an oil change more than annually, and that includes Diesels. I don't know anyone who has their car serviced more than once a year. What is different about the US? And think of the oil that is wasted...I know it gets recycled, but...
Mark Ryan @ Mar 14th 2008 6:28PM
The difference is likely driving distances. In the US, long freeway hauls are the norm. Maybe it's the same for Europe, but I'd wager Europeans generally do fewer than the 12-15,000 annual miles most drive in the US.
Colin Smith @ Mar 14th 2008 6:38PM
Not too sure about that, and I always thought that steady driving was kinder to engines than the short distance, cold-hot-cold stop-start driving so many of us here get up to.
I really do think this frequent oil changing is a legacy of the old days, when oils broke down rapidly, and that advertising must be successfully frightening motorists into spending money unnecessarily.
Guenther @ Mar 14th 2008 10:12PM
If you do long haul driving, you can definitely go longer.
Playdrv4me @ Mar 14th 2008 5:56PM
What's more important by the way isn't how often you change your engine oil, but rather how much the OTHER lubricants in modern vehicles are completely ignored.
One manufacturer recommendation for example that is absolutely ludicrous as far as I'm concerned is so called "Lifetime" transmission and gear oil. Often times, failure of these components in as little as 30 or 40000 miles (Escalade front differentials come to mind) is DIRECTLY attributable to loss of viscosity and neglect of fluid changes in these vital and HIGH friction areas.
Worry less about your engine oil and concern yourself more with what other fluids your vehicle might be begging for.
jfiv @ Mar 14th 2008 6:23PM
I've been doing 5K mile intervals for some time now. In fact, I got an 08 TL-S back in August and my oil life is now at 15%, with about 4800 miles on it. So I guess I'm doing something right...
KazO @ Mar 14th 2008 6:52PM
Contrary to popular belief, the BMW Service Interval system doesn't actually look at 'oil quality;' at least not in models since the late 90s. It primarily relies on fuel consumption, with cold starts and a couple of other factors added in. I've seen E46 non-M cars (nominally 15,500 miles) vary from 8000mi by leadfoots who track or autocross regularly, to 18,000 by freeway-only commuters.
One issue I've seen in some long-interval cases is that even though the oil may still be fine, filters can deteriorate to the point where pieces start sloughing off.
I do think that 3k is too often in most cases, and that there are multiple factors that could influence the interval, like sump capacity (look at what the change interval is on Porsches with 3 gallon sumps), filter quality, etc.
spdracerut @ Mar 14th 2008 7:39PM
People could always get their oil analyzed by companies like Blackstone Oil Labs. It's a good way to determine you're own personal oil change interval. I tend to change my oil often because I use WOT often and also spend a fair amount of time doing track days.
Frank @ Mar 14th 2008 7:43PM
My system: change oil every 5000 miles with the oil filter. That way I just have to look at the odometer. If the number is divisible by 5 then it's time to change the oil. That's for a used car with dino juice. For the wife's new car I use Mobil 1. After 5000 miles I change just the filter and add a little back in. At 10K I change the oil and filter. No problems with either car.
Gardiner Westbound @ Mar 14th 2008 8:17PM
I have put as many as 300,000-miles on a car with no mechanical issues whatsoever. My longstanding practice is to change the oil and filter the earliest of 3-months or 3,000-miles using a quality brand standard oil of the correct SAE rating and viscosity and an OEM filter. The transmission fluid and antifreeze are changed every second year.
Our cars are always serviced by a licensed mechanic. He checks it and provides early warning of small issues before they become big, horrible, expensive problems.
I am convinced preventive maintenance pays for itself. It is most certainly more convenient and less costly than the alternative, breakdown maintenance.
bruno @ Mar 14th 2008 8:38PM
I've had several vehicles with oil monitors. The longest interval was 18,000 miles and that was a BMW which the article says may monitor the actual oil quality. That was with a lot of highway miles (90% at least). So far, nothing has had engine problems, though I never keep them to 100,000 miles. A couple made it to the 90K plus range.
I suppose if you wanted to drive the wheels off it might pay to do more frequent changes.
Tony @ Mar 14th 2008 8:59PM
I try to change my oil every 7000 on my old 1987 honda accord 5spd. I never had any engine problem at all. The car had about 326000 miles on it until a garbage truck hit and got total.
JIm @ Mar 14th 2008 9:06PM
First off, oil never loses it ability to lubricate. It's the additive package that's consumed.
Some time ago I monitored a Ford Explorer forum where the "when to change" argument loomed large. A fellow with an older Explorer ('93, 67K miles) offered up his vehicle for a test of synthetic oil if someone would pay for the spec lab analysis. Someone did. He first did a baseline spec lab test which ensured everything was okay - it was. He then changed the oil to Mobil One and a Fram filter. At 5K miles he changed the filter and again did a spec analysis. He did it again at 10K and again at 15K. Spec analysis indicated that at each 5K interval another 1/3 of the additive package had been consumed, but there were no other negative indications. So at 15K the additive package was used up and it was time for a change.
Another story. Good college friend owned a Jeep Cherokee 4cyl, 5spd. Lives at 6,500' so given the altitude-density he had to drive the crap out of it to maintain speed. Used off-the-shelf dino oil, changed every 5K. Engine lasted to 275K and did not use oil. His wife drove it five miles with the temp light on - no water. He junked it because the body was shot which is exactly why changing at 3K doesn't make sense - saving the engine for the next guy.
I change with Mobile One every 10K in my current Explorer which now has 200K. Runs fine, compression is good an it doesn't use oil between changes.
It's an old article for sure, but in July '96 Consumer Reports did a write up on oil changes. They used NYC taxis and during engine rebuilds checked all the internals then changed oil 6K using dino oil, and 12K using synthetic. At the end of the two year test there was no wear difference between the two, nor were there any failures that could be pointed at oil. They did not feel the synthetic test was valid because two of the three cars had failures not related to oil and they didn't feel one vehicle was a good enough test.
For the most part we change too often, chalking it up to cheap insurance and I admit it's a big mental jump to move from 3K to 10, but it works for me. It's a small part but I feel better knowing I don't recycle nearly as much oil as I used to and my vehicles don't seem to know the difference. When I was a kid it was normal to overhaul (or "top end job") at 65-75K. The mfgrs would have a class action suit if that happened today.