I cringe when I’m in a group of people and somebody asks “How often should I change my oil?” Why? Because if you ask 5 different car guys this question you are likely to get 5 different answers. Some intervals have been driven into our heads such as the all too common – Oil change every 3000 miles. I’m seeing more and more evidence and practice that suggests 3000 miles is probably overkill and most oils will last longer than that. Sure your dad changed his oil every 3000 miles on his 57 Chevy Bel-Air and it’s lasted half a century, but the fact is that cars and oils are much more advanced these days. I’m not saying changing it every 3000 miles is bad, just that it deserves a closer look before dumping money into the engine that often.
Why not just do an oil change every 3000 miles?
You may have noticed that the cost of crude oil and all things related are constantly on the rise. When I first got my license 15 years ago I could buy a quart of oil for $0.88. Less than 2 decades later and the price has more than tripled with the no name brand oil reaching nearly $3 a quart. You can sometimes find it cheaper at Wal-Mart but the point here is that if you’re going to throw $20+ worth of oil into your car, you want to get your money’s worth out of it. If you change the oil yourself then you have to also factor in the time it takes you, because your time is worth something after all. If you pay to have it changed, consider that you have to make an appointment to drop off your car or wait for it to be done plus pay for the service. These are all things to consider when deciding if you really need to change your oil every 3000 miles.
Synthetic Oil Vs. Standard Oil
This could be another topic all on its own and will also cause controversy amongst a group of car guys, but I’ll save that for another time. The basics are that synthetics don’t break down as quickly and provide better lubrication than standard oil. Surprisingly for an oil to be labeled as “Full Synthetic” it need only contain 30% synthetic oil. TRUE synthetic oil costs upwards of $10 a quart and isn’t normally readily available. When most people say they run full synthetic oil, they mean the stuff that’s 30% synthetic. When it comes to engine oil you generally get what you pay for. It’s a compromise, you probably won’t get enough extra life out of synthetic oil to warrant the price jump, but when you factor in other benefits such as fuel economy and horsepower it’s an attractive alternative. This is all the more reason to consider changing your oil less frequently than every 3000 miles. So how often should synthetic oil be changed? I think you can get another 1000 or so miles out of it than you would a standard oil.
Think with your DipStick
If you check your oil regularly (which you should!) you’ll take notice that the oil darkens over time. It starts off as a nice light amber color and after some time begins to brown and eventually if you let it go long enough it will start to look black. This is the oil degrading over time due to heat and friction. If you pull your dipstick and the oil is still amber colored, you’ve got mileage left on the oil. If it’s starting to turn brown, you should consider changing it soon, and if it’s black then you should change it right away.
The Mileage Game
Most manufacturers, oil companies, lube shops, and mechanics are still going to tell you to change your oil at 3000 miles regardless of what the oil looks like. Why shouldn’t they tell you that, they stand to make money off from your need of an oil change. But how often do you NEED an oil change? Most unbiased opinions are closer to the 5000 mile mark, and there are some variables that apply here. For example, if you’re using a real bargain basement no name brand oil you might as well go ahead and change it every 3000-4000 miles because it’s not going to last much beyond that. However, if you are using a good mid-high grade oil or synthetic blend you should be able to get 5000 miles out of it no problem in most vehicles. I dare say that a good full synthetic oil such as Mobil 1 can bring you past 6000 miles for an oil change. It works for me and my vehicles but keep an eye on that dipstick and oil color. Depending on how you drive you might need a change sooner rather than later.
But my Oil Change light is on!
Many newer vehicles have a “dummy light” that tells you when to change your oil. There are some misconceptions out there about how these lights work. Some people think they are preset for a mileage, and some people think they somehow test the oil. Neither theory is correct. Most of these sensors actually count crankshaft rotations to decide when to change the oil. This means that driving at a higher RPM will govern an oil change at a lower mileage than driving at a lower RPM. It’s a good light for the average Joe because it reminds them to do maintenance on the car and that’s great, but it’s not the be all end all. Those lights don’t take into consideration higher grades of oil for instance. 1,000,000 rotations of the crankshaft with $2 a quart oil is going to be different than 1,000,000 rotations with $5 a quart synthetic oil.
How Often Should You Change Your Oil: The Bottom Line
It’s your car and you should do what you’re comfortable with. For me, that’s running a higher grade oil and changing it around 6000 miles. My oil still looks decent at that point (not new but not black). If you aren’t comfortable going that long, then by all means change it sooner there’s no harm that can be done by doing so. While car lubrication is on your mind be sure to check your transmission fluid regularly as well. It’s often overlooked and is just as important as checking and changing your engine oil.
I’d like to make a note here that SOME car manufacturers actually require oil changes at certain intervals to cover any engine warranty issues. If you’re car is under warranty you may want to check on that before making a decision about when to change your oil.