Oil's Well That Ends Well (Oil Change Grades and Weight)
April 23, 2023
Changing your oil regularly is one of the most important things you can do to keep your vehicle running well. And knowing the right type of oil to use is also very important.
Engine oil is classified by weight, but it doesn't refer to how much the oil would weigh if you put it on a scale. It refers to viscosity, or how easily the oil flows through the engine. Most engines operate normally at around 210°F/99°C. The viscosity, or weight, is assigned a number by how well it flows at that temperature. The lower the number, the more freely it flows.
Most vehicle engines use what's called a multigrade oil which behaves differently in different temperatures. Multigrade oils have a "W" in their viscosity number that you may have seen on a bottle of oil, something like 5W30. The W stands for winter and shows how freely it flows in colder temperatures.
That means a 5W30 oil will behave like a 5 weight oil in lower temperatures (less viscous or thinner) and a 30 weight oil in warmer temperatures (more viscous or thicker). That's important on a cold day because the oil needs to behave like a thinner oil when you start your engine since it need to lubricate engine components immediately to protect the metal components. Then as the engine warms up, it behaves like a thicker oil to prevent friction among those parts. Pretty neat trick, right?
The type of oil you use can differ depending on what type of climate you operate your vehicle in and how your vehicle is used (carrying big loads, towing, etc.). Your owner's manual contains several different recommendations based on these factors. Your service advisor can recommend the right oil for your needs. Like Shakespeare said, "Oil's well that ends well."
Auto Lab Troy
2790 West Maple Rd.
Troy, Michigan 48084
(248) 643-7690
Need Service?
More articles from Auto Lab Troy

Cabin Air Filter and Engine Air Filter: What?s the Difference?
March 8, 2026
You may have heard someone say they just got the air filter replaced in their vehicle. But did you know your vehicle has two different major air filters and they both perform quite differentbut very importantduties? Todays vehicles have a cabin air filter, and an engine air filter. The engine a... More

Why is My Brake Pedal Hard to Push?
March 1, 2026
When you push on your brake pedal, you should find your vehicle easy to stop. But at some point, you might notice stopping takes much more pressure on the pedal than it used to. When it gets to that point it becomes a safety issue, and you should bring your vehicle in so we can track down whats... More

Power Steering Pump Replacement
February 22, 2026
When youre driving and you hear a squeal or groan when you turn, it may be a sign your power steering pump is on its last legs. The same is true if you feel your steering is slipping or doesnt respond to your hands like it used to. Precise, responsive steering is, of course, important when it ... More
