101 Facts About Oil Changes in 2021

Are you making sure to change your car’s oil at the proper interval? Good for you! There’s really not a better task you can do to keep your car running than changing the oil on a regular schedule.  We know finding facts and figures about oil changes can be time-consuming and frustrating, so we put together this list of the top 101 facts, notes, and statistics so you can easily reference them and refer back to them any time in the future.  This space is constantly changing, so if you see a fact that is not up-to-date, feel free to let us know. And if you know a stat that we should add, let us know that too!

1. The purpose of oil lubricates the parts of the engine so they don’t grind against each other.

With this very specific reason, it is essential to change oil on time to keep the engine from overheating, and it carries away dirt, dust, and other contaminants that would otherwise clog up the engine parts. 

2. The oil change interval required for your vehicle will vary depending on its age, the type of oil used, and your driving conditions.

To know as to when the exact time interval to change oil is to check the car manufacturer’s manual or check more information online for reference.

3. With today’s upgraded oils, the oil change interval for most engines is now between 5,000 to 7,500 miles.

4. You could even go as far as 15,000 miles between services if you use full-synthetic oil.

5. Drivers should not rely on the dashboard warning light before changing the oil.

Some dashboard lights are programmed to come on automatically at 3,000-5,000 miles after the last oil change. In some cars, that light might not come on until the engine is already too low on oil. 

6. Engine’s temperature affects oil’s viscosity.

7. The Society of Automotive Engineers (SAW) has developed designations for oil that indicate the viscosity of the oil, for example, 10-30W oil.

The “10W” corresponds to the lower viscosity when the engine is cold. The “30” refers to the higher viscosity when the engine is hot and running normally. 

8. Conventional motor oil is a lubricant that is derived directly from crude oil.

It has excellent properties that allow it to provide lubrication at high temperatures, as well as maintaining its stability over long periods of time.

9. Full synthetic oil uses a synthetic base stock mixed with a variety of additives that boost the performance of the oil. 

While all synthetics on the market may offer a higher level of protection than conventional or synthetics blends, not all synthetics are equal. 

10. Synthetic blend oil is a mix of conventional motor oils and synthetic base stocks. 

Because of the added synthetic base stock, you’re going to get more performance and protection than you would by using a conventional oil alone.

11. Over the course of two years and 30,000 miles, assuming that your oil change costs $40 a pop, you could save $240 if you get it changed every 7,500 miles vs. every 3,000 miles.

12. Oil becomes less effective as it ages, and by not getting the engine warm enough, excess moisture that forms in the engine will not be removed, which can lead to shorter engine life.

Even if you drive fewer miles each year than your automaker suggests changing the oil (say, 6,000 miles, with suggested oil-change intervals at 7,500 miles), you should still be getting that oil changed twice a year.

13. Short trip driving takes a serious toll on motor oil because the engine never warms up enough to boil off the moisture and acids that accumulate inside the crankcase.

Be sure to get an oil change and replace the oil filter as recommended under the “severe service” maintenance interval listed in your owner’s manual.

14. A high motor oil viscosity number doesn’t necessarily provide better protection.

Consult your owner’s manual to ensure you’re buying the right oil based on your motor and driving conditions.

15. If the engine’s oil is milky brown when examining it, there’s likely coolant in the oil—a condition that can be caused by a blown head gasket, cracked casings, or a failed transmission cooler. 

In any of these cases, your car will require immediate servicing by a technician.

16. You will want to consider synthetics if your vehicle has a supercharged engine, is used for towing, or tends to be operated in extremely hot or cold climates.

17. Racing oil is a special blend of oil designed for the rigours of high speeds—not for daily driving.

18. Racing oil contains three times more anti-wear and friction reducing additives (for less wear and more horsepower) than ordinary oil.

Running racing oil in a non-track vehicle can increase the likelihood of sludge buildup in the engine and it can damage the $1,200 catalytic converter.

19. Race teams use lower-viscosity oil with more friction modifiers to qualify. Then they change to a higher-viscosity oil for the race.

20. Racing teams go through racing oil at the rate of about 1,900 litres of oil per car, per season.

21. In a typical NASCAR race, oil temps can run as high as 160 degrees C.

22. Teams analyze the oil after every race. 

They check for viscosity change, the level of metals worn away, oxidation (indicates how the oil held up to heat) and additive depletion.

23. “W” in 10W-30 stands for “winter” and not for “weight”.

Because oil viscosity changes with temperature, the multi-grade rating gives you both the hot and cold viscosities. 10W represents the oil’s viscosity rating for winter use.

24. Synthetic engine oils can’t wear down seals in an engine and cause leaks.

Synthetic oil has not been shown to deteriorate engine seals or gaskets. But it might find an existing leak. The smaller molecules of synthetic oil are able to pass through very small cracks and crevices that the larger molecules of petroleum-based oil cannot. 

25. Engines will not benefit if one uses supplemental additives.

Additional additives may dilute the effectiveness of the oil or even upset the oil chemistry.

26. Once you use synthetic oil, you can still switch back to conventional oil.

 In fact, synthetic blends are a mixture of synthetic and conventional oil.

27. Get in the habit of checking your oil at least once a month to ensure your car’s not leaking or burning oil.

28. Good oil should be a clear brown-black color.

29. If the oil is murky or opaque, it might be time for a change.

30. Quality motor oil recommended by your vehicle’s manufacturer does not break down after 3,000 miles.

31. Changing your oil is great preventative maintenance, but it should be done in accordance with the manufacturer service intervals.

32. The easy-to-remember 3,000-mile interval actually creates more confusion as to the real maintenance needs of your vehicle. 

Thus, it is easier to follow factory guidelines, more economical, and more appropriate.

33. The traditional view that 3,000 miles is best for your car is old school, wasteful, and fails to appreciate today’s mechanical and oil technologies.

34. Used motor oil can contain toxic substances such as benzene, lead, zinc, and cadmium.

35. The oil from a single oil change (1 gallon) can ruin the taste of a million gallons of drinking water (1 part per million), the supply of 50 people for one year.

36. Films of oil on the surface of water prevent the replenishment of dissolved oxygen, impair photosynthetic processes, and block sunlight.

37. Oil dumped on land reduces soil productivity.

38. Concentrations of 50 to 100 parts per million (ppm) of used oil can foul sewage treatment processes.

39. In the U.S., less than 60 percent of used oil is recycled.

40. 1 in 5 households have a do-it-yourself (DIY) oil changer.

41. As of July 2004, there are more than 2,600 State-certified collection centers and 70 curbside collection programs in California, which accept used oil for free.

42. More than 98 million gallons of used oils were recycled in the fiscal year 2001-2002.

43. 2.5 quarts of re-refined lubricating oil can be produced from one gallon of used oil.

44. The United States Postal Service and National Park Service use re-refined oil in their vehicle fleets.

45. The Department of Defense compared making lube oils from virgin base oil and used oil and determined using used oil was both more environmentally friendly and cost-effective.

46. The U.S. Conference of Mayors has endorsed re-refined oil.

47. Each year the U.S. generates 425 million used automotive oil filters containing 160,000 tons of iron units and 18 million gallons of oil.

48. Recycling all the filters sold annually in the United States would result in the recovery of about 160,000 tons of steel, or enough steel to make 16 new stadiums the size of Atlanta’s Turner Stadium.

49. Used oil filters can contain more than 45 percent used motor oil in weight when removed from the vehicle.

50. 91.3 million gallons of used lubricating oil were recycled during 2005, which was 5 percent above the 87.0 million gallons collected in 2004.


51. Sludge is a tar-like residue that can build up in an engine as the result of oil thickening or breakdown, most often the result of too-infrequent oil changes.

High mileage oil can help remove engine sludge and reduce wear in older engines.

52. Over time, an engine’s seals can erode, causing engine oil to leak.

Additives in certain high mileage oils can help protect worn seals and keep leaks from forming. 

53. In cold weather, thin oils reduce friction and help engines to start quicker.

54. In higher temperatures, thick oils maintain oil pressure and film strength, and support heavier loads.

55. The viscosity index measures oil’s ability to resist changes in viscosity as temperature changes.

Most multi-grade motor oils are formulated with viscosity index improvers, which use polymer additives to help maintain consistent oil viscosity over a wide range of temperatures—protecting engine parts from wear. 

56. The usage of animal fat and vegetable oil evolved into the use of motor oil made from crude oil; and later came the invention of synthetic oil.

57. The innovation and forward-thinking culture of Shell, helped them develop a full synthetic motor oil made from natural gas. This patented process is known as PurePlus Technology.

58. High-Mileage Motor Oil is formulated with unique additives, high-mileage motor oil helps to reduce oil burn-off and prevent oil leaks that can occur in older engines.

This oil is designed for newer or late model vehicles with more than 75,000 miles.

59. Today’s motor oils are categorized based on a rating system developed by the Society of Automotive Engineers (SAE), which rates oils by viscosity.

60. Another symbol that commonly appears on motor oils is the API “donut.” API stands for the American Petroleum Institute, which offers a stamp of approval to help customers find engine oils that meet the minimum standards set by engine and vehicle manufacturers.

61. The API symbol has three parts: the top half of the circle, which indicates the API service rating, the center of the circle, which displays the SAE viscosity, and the lower half of the circle, which tells you the oil’s energy-conserving properties.

62. When motor oil is doing its job, it will lubricate the parts in your engine and as a result, keep the engine quiet. However, if your oil level is low or has completely run out, you may start to hear knocking or rumbling sounds.

If you hear engine noise , take your car in for an oil change immediately.

63. Smelling oil inside your car is a sign that you may have an oil leak. If you ever smell exhaust fumes or gas, your vehicle may be overheating.

You’ll want to take your car in for a maintenance check as soon as possible in either case.

64. It’s normal for your car’s tailpipe to emit translucent vapor, but if you ever notice that this turns to smoke, you may have an oil leak or faulty engine parts.

65. An oil change will cost you about $40.

This service usually includes checking and topping off other fluids such as brake fluid, windshield washer fluid, and power steering fluid. This service may also include checking your tire pressure and the condition of your brakes. 

66. Adding new oil instead of changing your oil completely can be a smart move if your oil is running low, but only if it is still relatively clean. 

If your engine is already full of old, dirty oil, however, adding new oil will only exacerbate the issue. 

67. Even if your engine is full of clean oil, too much oil can cause damage—no matter how clean it is.

Adding too much oil to your vehicle can build up the pressure in your engine, compromising seals and gaskets and creating leaks.

68. Motor or engine oil helps regulate the temperature of your engine and keeps it from overheating.

69. Oil can carry away small debris like dirt and dust to keep it from clogging your engine.

70. Having the correct oil pressure assures you that your engine is being lubricated properly and protecting your engine from premature wear.

Always use the correct motor oil that the manufacturer recommends for your vehicle.

71. The oil filter removes and traps any contaminants from the oil.

Over time, the filter becomes clogged and reduces oil flow and must be replaced when the oil is changed.

72. Spark Plug is a part of the engine that sends electric sparks to make the gasoline burn and keep the engine running.

73. Main Bearings are located between the crankshaft and engine block, helping to avoid friction between the two.

74. Piston Rings  maintains gas pressure between the piston and the cylinder wall.

75. Cylinders are walls where pistons travel between, this is the central aspect of the engine.

76. Crankshaft is rotating inside the main and wall bearings, the crank changes the up and down motion of the pistons to a rotation.

77. Diesel motor oils contain higher amounts of additives than gasoline motor oils because diesel engines tend to be dirtier.

 When it comes to the labor involved, diesel engines don’t really require any extra care, though they do tend to need more frequent oil and filter changes.

78. Diesel motor oils contain higher amounts of additives than gasoline motor oils because diesel engines tend to be dirtier.

79. In recent years, a suction method (known as “siphoning”) has experienced a gain in popularity. These new siphoning machines, using a method adapted from motor boats, attach to the dipstick and suction oil out of the engine.

 There’s some disagreement on which method removes oil the best, but everyone agrees that getting your oil changed is a must!

80. Motor oils do not just mean engine oil. A number of mechanical components are like transmission and brakes use their respective motor oil. 

 Make sure to get them replaced as needed.

81. Commonly known as the ‘Dark Oil Myth’, partially dark motor oil does not indicate an oil change.

Make sure it is replaced at the right oil change interval, either after a certain number of kilometres have been covered, or in terms of sheer time lapse.

82. Getting motor oil changed too frequently won’t do any good. 

Change the oil only if it benefits the vehicle. Non-synthetic oils should undergo replacement at 5000km intervals.

83. During the process of adding new oil, you also receive a new oil filter as well. 

At some service intervals, your vehicle may also need a new oil pan drain plug as over time the threads wear down.

 84. The old oil is disposed before replenishing. 

While this concludes the process of an oil change, a mechanic may suggest maintenance on other parts of your vehicle if necessary.

85. Checking your oil regularly despite the time frame of needing a change can more than likely prevent you from having to spend a ton of money on a new engine due to burned oil later on down the road. 

 Your car, truck, or SUV’s engine has a dipstick which is marked for low, high, and operating levels of engine oil.

86. It is recommended you check the oil level in your vehicle’s engine either prior to starting it or after waiting 5-10 minutes to allow for the oil to drain properly down into the oil pan for measurement.

87. A typical oil change usually will take between 30 and 90 minutes, sometimes longer depending on the circumstances.

88. There are 6,857 oil change and lubrication shops in the United States.

89. In February 2020, on average, Friday was the busiest day of the week for oil change and lubrication shops.

90. In February 2020, Utah was the state with the highest foot traffic per capita to the oil change and lubrication shops.

91. Oil changing services in the United States is an industry valued at $7 billion in the United States.

 Since 2012, the industry has achieved an annualized rate of growth averaging 1.5%. (IBIS World)

92. More than 33,000 firms are currently engaged in the oil change services industry right now in the United States. 

 They are responsible for the direct employment of almost 90,000 people.

93. 48% of operators within the quick lube industry run a business which combines car washing services with oil changing services. Another 22% of operators combine automotive repair with quick lube services.

94. The average price for a multi-point oil change within the quick lube industry is $36.82. If a synthetic oil change is requested, the price of the oil change jumps to $70.31.

95. Just 29% of vehicle owners take their oil changes to a business other than the dealership where they purchased their vehicle. 1 in 3 vehicle owners decide to change their own oil after purchasing a new vehicle.

96. In the United States, about 450 million oil changes are performed each year. There are about 250 million vehicles on the road which will require services at some point that can be provided by a quick lube location.

97. Even though quick lube locations are seeing a reduction in the number of cars being serviced each day, the number of oil changes being performed is rising. In 2013, there were an average of 37.8 vehicles serviced per location, with 32.9 oil changes performed per day.

98. The average age of a vehicle owned in the United States is 11.4 years.

99. The average vehicle owner will change their oil about every 5,000 miles.

100. Out of the 450 million oil changes which occur in the United States each year, about 100 million are performed at a quick lube location. 16% of the oil changes which occur within the quick lube industry feature Valvoline products.

101. Consumers are shifting toward premium products within the quick lube industry. In 2011, 31% of consumers preferred a premium product. In 2016, 45% of consumers asked for premium products from their preferred quick lube business.

Are You Looking for an Oil Change Shop You Can Trust?

If you’re considering making a change to an independent auto repair mechanic trusted by thousands of happy customers, look no further than autoTECH Blackhawk. Why? We differ from other automotive repair shops because we are a relationship shop. This means that the more of your car repair needs we support you with, the better able we are to customize our recommendations based on your driving habits and needs. Whether you want to keep the daily driver in ‘good enough’ condition, style your new car so that it’s customized just for you, maintain your favorite car in ‘like new’ condition, or even train your whole family to be more knowledgeable about cars – we partner with you to ensure that your cars meet your needs. We also offer an industry-leading 3-Year/36,000 mile warranty, so we only use Original Equipment and manufacturer recommended products. Contact us now to book your no-contact, friendly appointment! We truly value your trust and your business, so thank you for staying local with your auto repair needs.

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