You already know you should change your car’s oil—or have it changed by a professional—every 3,000 to 5,000 miles. But if you’ve ever gone to the store to buy a new container of motor oil and seen the large variety of options or had a mechanic ask you what type of oil you want, you may have felt overwhelmed. You see or hear the terms “viscosity” or “synthetic blend” and wonder what in the world it all means.
How do you know which oil is best for your car? Do you have options for your particular car? What factors play into the type of oil you should use? In this blog, we answer all of these questions, and help you understand how to pick the right motor oil for your vehicle.
Reading the Labels
There are two labels that you’ll find on each container of motor oil. One is called the “starburst” and the other is the “donut.” The American Petroleum Institute (API) put together these labels to let consumers know important details about the oil.
The “starburst” label lets you, the consumer, know that this oil meets minimum standards. These standards were put together by the International Lubricant Standardization and Approval Committee (ILSAC) and are updated when necessary. You can find the “starburst” label at the front of the oil container.
The “donut” label is a little more complex and is usually located on the container’s back. There are three parts of this label: the top portion, the bottom portion, and the circle in the center. The top half of the donut tells you the API service rating—specifically, the type of performance the oil provides. The bottom section of the donut tells you the oil’s specific energy- or resource-conserving properties, if applicable. The donut’s center tells you the oil’s viscosity.
In the simplest terms, viscosity is how resistant a fluid is to flow. On a container of oil, you’ll see viscosity indicated in the format of “#W-##”. The number before the “w” indicates the oil’s flow at a temperature of 0℉. The numbers after the “w” indicate the oil’s flow at 212℉. The “w” doesn’t stand for weight, as most believe, but for “winter.”
The lower the number before the “w”, the less the oil will thicken when cold. If you live in a cold climate, you may benefit from using oil with a lower first number like 5W or 0W. The lower the last number, the more the oil will thin in the heat, so if you live somewhere hotter, you may want oil rated at 40. Of course, you need to check your car’s owner manual to see what the safety parameters are for that specific vehicle.
Picking an Oil
Now that you know how to read the labels and you understand what viscosity is, it’s time to actually decide on an oil. You have a variety of options that work for different types and ages of vehicles.
Conventional oil is the cheapest oil available. Conventional oil comes in a variety of quality levels and viscosity grades and is generally what’s used at dealerships. If your car has a simple engine design and is driven regularly but not too often, conventional oil is probably the best choice for you.
Premium Conventional Oil
If your car is newer, premium conventional oil is the standard option. Most premium oils can be found in most common viscosities, which work for most light-duty vehicles. Both conventional and premium conventional oils are organic.
Full Synthetic Oil
Full synthetic oils have been chemically engineered for technologically advanced engines. The viscosity range of full synthetic oil is usually wider, and full synthetic oil has high-performance additives. You may think this option is the best choice for any vehicle; however, it can be three times the price and is usually not necessary according to the vehicle’s owner manual.
Synthetic Blend Oil
A synthetic blend is a combination of conventional and synthetic oils. These oils work perfectly for high-load vehicles like SUVs and pickup trucks. In extreme temperatures, synthetic blends feature better viscosity ratings than regular conventional oil. Unlike a full synthetic oil, synthetic blend oils are only slightly more expensive than conventional oils.
High-mileage oil is exactly what it sounds like: an oil designed for vehicles with mileages over 75,000 or late models. More than half the vehicles being driven today have a high mileage and need the additives that high-mileage oil provides to stay on the road longer. These additives expand the viscosity ranges and reduce the risk of oil burn-off and leaking.
Of course, before making any decisions you should check your vehicle’s owner manual. It offers recommendations on types of oil to use and viscosity ratings to look out for. If you have any further questions, ask your dealership or mechanic what they recommend.