Oil Weights and What They Mean

Oil is what keeps your engine going, but many of us don’t understand what the various weights mean and when you should use them. Not only is keeping up on your oil changes important, but using the right type of oil for your vehicle and driving conditions is also integral to the proper operation of your vehicle.

The Role of Oil in Your Engine

Before we start diving into oil weights, it’s good to know what oil does for your vehicle. Oil plays a vital role in keeping your engine running smoothly. Your engine is full of quickly moving parts, and all of that metal-on-metal rubbing can take its toll if there isn’t proper lubrication. Oil prevents your engine from overheating as well as creates a barrier between the parts so that they don’t scrape up against each other and wear out or get damaged.

Oil Weights Explained

Oil weights indicate the viscosity of the bottle of oil and tell us how the oil will perform under various conditions. Oil weights are established by the Society of Automotive Engineers (SAE), which has set parameters for the classification of oil based on typical engine temperatures. Most engines operate at 210 degrees Fahrenheit, so the weights are based on performance at this temperature.

You may see oil weights as just one number, or most likely, you’ll see a multigrade oil rating which gives a winter and standard viscosity. A couple examples of multigrade oil weights are 5W-20 or 10W-30. Let’s take 10W-30 as an example. This means that in cold weather, not typical here in Ontario, California, the oil acts as a 10-weight oil at start-up. It’s a bit thinner allowing it to spread and move more easily between parts at cooler temperatures. As the engine and oil heat up, it will act as a 30-weight oil, becoming a bit thicker and standing up better to the hot conditions of the engine.

What oil should you use?
Your vehicle’s manufacturer will make a recommendation for the type of oil you should use which will be a conventional or a synthetic oil. Conventional oil starts with a petroleum base and uses additives to allow for multigrade performance. These oils work well, but tend to get “used up” more quickly than synthetic oils, meaning that you’ll likely have to have more frequent oil changes to keep your engine in good running order. Synthetic oils are man-made and multigrade options are designed for that specific performance, without the use of additives. They just simply are multigrade. Most newer cars are manufactured to use synthetic oil as it generally functions better and lasts longer, leading to the need for fewer oil changes for standard use while also offering the best protection.

Oil Weight Clarified
Now that you know the role of oil in your vehicle, and how the weights are assigned, you can understand a bit more about how your engine works and why it needs proper lubrication. The best course of action is to keep an eye on your engine’s oil change light, check your oil on a regular basis with the dipstick and then use the manufacturer’s weight recommendation for any oil changes.

Get an oil change
Contact any of our car dealerships right here in the Inland Empire to learn more about our service departments and how we can help you keep your engine running smoothly with regular oil changes.