What does oil do in a car?

Have you ever wondered, "What does oil do in a car?" Or, "Do I really need to change my oil that often?" Despite being one of the most important vehicle maintenance tasks you can do as a car owner, for many Canadians, oil changes are one of the most frequently postponed.

From lubricating engine components to reduce friction to regulating your engine temperature, your motor oil plays a critical role in the overall health and longevity of your vehicle. Whether you're buying a brand-new vehicle or shopping in the used car market, knowing what type of oil your vehicle needs can save you from costly repairs and optimize performance levels.

Canada has a diverse climate throughout the year, which is why paying attention to your oil maintenance is even more important. Without clean oil that matches your engine type, your vehicle can suffer excess wear, poor fuel economy, and reduced efficiency.

In this guide, we're answering your top questions about what oil does, when to tell you need an oil change, how to perform this type of car maintenance yourself, and more! Stick around for more info.

What’s the function of motor oil in a vehicle?

Oil is considered by most automotive experts to be the lifeblood of the car. Similar to blood in the human body, oil is necessary for the engine to function. Your engine relies on oil to keep its numerous working parts operating as they're intended to do. More specifically, your engine oil:

1. Lubricates engine components

As your engine operates, metal surfaces within the engine itself are constantly moving and rubbing against each other. Without lubricating oil, the friction would quickly wear down the metal components, causing damage to your vehicle. The lubricating oil, therefore, acts as a coating to these components to reduce friction, which minimizes wear and tear. The result? A car engine that operates smoothly and efficiently.

2. Reduces heat

As you drive your vehicle, the engine parts generate extreme temperatures. The oil moves this heat away from certain engine parts to prevent overheating.

3. Prevents rust and corrosion

Having good quality engine oil that contains additives to prevent oxidation helps deter the rusting of your engine components. This is especially important in Canadian regions where road salt, snow, and high humidity levels can lead to corrosion over time.

4. Seal small gaps between parts

Motor oil also seals tiny gaps between engine parts. By doing so, it prevents combustion gases from escaping the combustion chamber, while also optimizing engine power and fuel economy.

5. Traps and suspends contaminants

Engine oils also contain detergents that trap dirt, metal particles, and other contaminants. These impurities are then trapped in your oil filter, which helps keep your engine cleaner for longer. Ultimately, failing to perform oil changes on your car can lead to engine failure and thousands of dollars in repair bills.

The different types of engine oil

58% of Canadian drivers are unaware of the differences between synthetic and conventional oil. But did you know there are four types of oil available for vehicles? Here's what you need to know:

Conventional oil

Conventional oil is a product of crude oil. In terms of motor oil, conventional oil is the most standard and affordable option. If you have an older engine and are pretty on top of your vehicle maintenance, topping up your car with conventional oil is enough. Conventional oil is also ideal for those living in milder climates and those who drive short distances. That said, compared to synthetic oils, conventional oil breaks down at a quicker rate and is unable to handle extreme temperatures as well.

Synthetic oil

Synthetic oil is created in a lab and intended to maximize your engine's performance levels. It excels at stabilizing high and low temperatures and offers longer engine protection. For Canadians, synthetic oil is ideal, especially in the wintertime, when there are long periods of cold temperatures. It's also the preferred engine oil for high-performance engines found in sports and luxury vehicles.

Synthetic blends

Synthetic blends contain conventional oil and synthetic oil properties. This option offers better performance than conventional oil at a more affordable price than fully synthetic oils.

High-mileage oil

High-mileage engine oil is designed specifically for older engines with higher mileage. These engine oils contain additives to reduce engine wear and minimize oil consumption. Ultimately, if you have an older vehicle you want to continue driving, this type of oil is recommended.

How to choose the right oil for your car

Choosing the right oil for your car can be confusing, especially because there isn't a one-size-fits-all answer. It really comes down to the age of your engine, your driving habits, the average climate in your area, and what your vehicle manufacturer recommends.

For example, if you drive a 2022 Honda Civic, you may opt for synthetic motor oil to maintain the efficient operation of your vehicle. In contrast, if you drive a 2010 Ford Focus with 150,000 kilometres on it, you may want to consider a high-mileage engine oil to reduce engine wear and maintain a better fuel economy as your car ages. Check your owner's manual for your car manufacturer's recommendations for your specific vehicle. Below, you’ll find a comparison table for car engine oils:

Car oil comparison table

Mechanics 101: How oil flows through the engine

When you pour motor oil into your engine, it flows through an intricate system designed to protect and power your vehicle. Here's how it works:

1. Starts in the oil pan

The engine oil starts in what is known as an oil pan, which is located at the bottom of your vehicle's engine. When you start your vehicle, the oil pump pulls the motor oil from the pan, sending it through the engine.

2. Pumps through the oil filter

Before moving to the engine, the motor oil is pumped through an oil filter. This filter traps sludge buildup, metal particles, dirt, and other impurities to ensure the oil that circulates through your engine is clean, which reduces engine wear and tear and prevents clogging.

3. Circulates to engine parts

The now filtered engine oil flows through the engine to lubricate different engine parts that experience the most friction and high temperatures, including:

• Crackshaft

• Bearings

• Piston rings

• Cylinder walls

• Camshaft

• Calve parts

4. Manages high and low temperatures and friction

As the motor oil circulates through the engine, it carries the generated heat away from the parts to regulate the engine temperature.

5. Returns to the oil pan

Once it's completed its job, the oil drains back into the oil pan, where it goes through the cycle once again. Older engines are more likely to experience oil circulation issues, especially in areas of Canada that have freezing winters and hot summer temperatures. For example, in colder provinces, the motor oil can thicken and circulate more slowly, leading to faulty engine parts, which is why a high-quality engine oil and regular oil changes are essential.

When and how often should you get an oil change

Changing your engine oil regularly is essential to keeping your vehicle running smoothly and safely. Unfortunately, there are a lot of misconceptions out there on how and when to change your oil, which can lead to confusion and, in some cases, engine failure. Luckily, we've cleared things up for you down below:

Recommended oil change intervals

A 2022 survey by the Canadian Automobile Association (CAA) indicated that 65% of Canadian drivers change their oil every 5,000 to 7,500 km. But does this apply to every vehicle? It depends! How often you change the oil in your car depends on several factors, including your vehicle’s age, your driving habits, and the type of oil used. As a rule of thumb:

• Conventional oil: Every 5,000 to 7,000 kilometres.

• Synthetic oil: Every 10,000 to 15,000 kilometres.

• Synthetic blend: Every 10,000 to 12,000 kilometres.

• High-mileage oil: Every 8,000 to 12,000 kilometres.

Tip: Follow your engine manufacturer's recommendations

When in doubt, always refer to your owner's manual for information regarding your vehicle. The manual should contain information like how often you should change your car's oil and what type of oil it takes based on your vehicle's make and model. Most modern vehicles come with an oil change light that will illuminate on your dashboard when your engine oil ages.

Myths vs. facts about your car's engine oil change

Have you fallen for any of these myths? We've debunked some of the most common below:

Myth: "You need to change your car's engine oil every 3,000 kilometres." This is false. Modern engines and synthetic oil can last up to 15,000 kilometres before needing to be changed.

Myth: "Dark oil means it's dirty." Not always. Oil naturally darkens as it collects heat from your engine, and when the additives in the oil itself activate. Instead, you'll want to check your engine oil's consistency. If the oil is gritty, it's likely because of sludge buildup, which indicates that it should be changed.

Myth: "If you don’t drive frequently, you don’t need regular oil changes." Even if you're not actively using your vehicle often or driving long distances, the oil within your oil pan will still degrade. So, regardless, you'll want to change the oil in your car every 6 to 12 months.

Signs you need an oil change

Knowing when it's time to change the oil in your car is essential if you want optimal performance and to prevent engine failure. While it's recommended that you book an oil change according to the recommendations outlined in your owner's manual, here are some telltale signs you can watch out for that indicate your motor oil change is well overdue:

Engine noise

Old oil, or when there isn't enough oil in your oil pan can put friction on your engine components. The rubbing on the metal surfaces can cause an increase in engine noise, like grinding or knocking. To keep your engine quiet, regular oil changes are needed.

Reduced engine performance levels

If your vehicle feels less responsive or sluggish, it could be because you need an oil change. For example, your vehicle is slow to accelerate, it may be because your motor oil is dirty and thicker than it needs to be, reducing its ability to flow smoothly through your engine. In turn, your fuel economy will diminish as your engine will need to work harder than normal.

The oil change light is illuminated

Take a look at your dashboard to see if your oil light is on. Most newer vehicles have sensors that measure oil pressure and quality. If it's illuminated, it's time for an oil change.

Excessive exhaust smoke

Excessive exhaust smoke can indicate burning oil due to worn seals or valves within your engine, leading to reduced engine performance and higher engine operating temperatures, which are dangerous and should be addressed quickly.

Overheating engine

When your engine is old or low, it can increase the operating temperature of your engine. When you fail to conduct an oil change on your car promptly, parts within your engine can be damaged, leading to engine failure, which can cost you thousands of dollars to repair.

There is an oil smell in your car

If there is an oil smell in your vehicle as you drive, it could indicate that you have an oil leak or that the oil itself is burning. This will usually pair with your engine overheating and your exhaust fumes being darker than normal. While these signs will tell you when it's time to book an oil change, when in doubt, you can always check the dipstick located under your hood.

How to check your car's oil

Checking your engine oil is a fairly simple task that can help you prevent costly engine troubles later down the road. It only takes five to ten minutes and doesn’t require any tools beyond those you'd already find in your household. Here's how you can check your motor oil at home:

Tools you need

Before changing your oil, have these tools ready:

• Clean towel or paper towel

• Disposable gloves (optional)

• Flashlight if you're working in an area with low lighting

• Your owner's manual (usually in your glove box)

Safety precautions

For safety, do the following before changing your car’s oil:

Turn off your engine

Make sure your car is turned off and it's been off for 10 to 15 minutes. This will give the oil enough time to settle into its pan, which is needed if you want an accurate reading and to prevent you from burning yourself on engine parts and the motor oil itself.

Your step-by-step

Use the steps below to change your engine oil:

1. Pop the hood of your car: Locate the hood release button under your dashboard. Open your hood and secure it in place with your prop stick.

2. Find the dipstick: Look for a bright coloured dipstick under your hood. Most of the time, it will either be yellow or orange. Pull the dipstick out.

3. Wipe it clean: Use your clean towel or paper towel to remove all oil from the dipstick before putting it back in.

4. Take the dipstick out: Then, take the dipstick out once again. This second reading shows the current oil levels in your car.

5. Read your oil level: The dipstick will have “Min” and “Max” indicators. Your oil should fall closer to the “Max” line.

6. Check oil quality: Clean oil is an amber shade, smooth, and somewhat transparent. If the oil is dirty, it will be a dark brown or black colour, gritty, or have a thick consistency.

7. Top up if needed: If your oil is low, remove the oil filler cap and add your oil based on what your manual says. Pour carefully to prevent any spills. Reinsert the dipstick and check your oil levels after more time to ensure it's at the optimal amount.

Pro Tip: Want to stay on top of maintenance? Check out our free Canadian Car Maintenance Checklist, including our pre-road trip maintenance, and hybrid/electric car maintenance checklists to ensure your vehicle runs safely year-round.

What happens if you don't change your engine oil regularly?

Skipping out on your regular oil changes might not seem like a big deal until the damage is done. Remember, your engine oil plays a crucial role in keeping your vehicle operating smoothly. When it becomes too old or dirty, it will no longer be able to keep your engine clean or protect its components from wearing down. Here's what could happen:

Engine wear and overheating

Motor oil reduces friction between the engine components, serving as both a lubricant and an engine coolant. As oil breaks down over time, it loses its ability to protect the engine from the constant friction. As a result, your engine parts will experience premature wear that can be expensive to fix. At the same time, when your engine operates at higher temperatures, it can warp internal parts, leading to permanent vehicle damage.

Costly repairs and total engine failure

We all get busy and push vehicle maintenance to the end of our to-do lists. But if you ignore changing your motor oil for long, it can create sludge buildup, which prevents lubrication of your engine's moving parts. Eventually, your engine will fail and cost more to fix than what your vehicle is worth. For example, potential costs you can incur include:

• Replacing piston rings or camshafts: $1,000 to $5,000.

• Engine replacement: $45000 to $10,000 or more.

Voided car warranties

If your car is still relatively new, meaning you bought it in the last two years, it may still be under its manufacturer's warranty. Most vehicle warranties require routine maintenance, including oil changes, to be performed regularly as a condition of keeping the protection valid. If you skip out on your motor oil changes and this leads to engine troubles, your claim could be denied. This means you’ll be stuck covering all repair costs out of pocket, yourself.

Environmental considerations: recycling used oil

Changing your engine oil is just as important as recycling your used oil the right way. Even one litre of used motor oil can contaminate up to one million litres of fresh water. Used motor oil is considered hazardous waste by Environment Canada, which is why it needs to be handled and disposed of correctly. The following presents the environmental impacts of used oil and an overview of its recycling:

Impact on our environment

When used motor oil is dumped in the trash, poured down your drain, or thrown on the ground, it's unable to break down as needed. Instead, it'll seep into your soil and groundwater before poisoning local wildlife, damaging the environment, and posing a health risk to you and your neighbours.

In Canada, an estimated 215 million litres of used oil are generated each year. Luckily, a substantial portion of this used oil is recycled correctly, largely due to federal and provincial programs.

How used motor oil is recycled

Used motor oil can be:

• Refined into new lubricating oil.

• Used in asphalt to pave roads.

• Oil filters and containers can also be recycled!

How to recycle oil in Canada

Recycling used engine oil is managed on a provincial level by organizations like the Used Oil Management Associations of Canada. What's convenient about these programs is that you can easily drop off your used motor oil for free at:

1. Auto repair shops.

2. Hazardous waste facilities in your community.

3. Canadian Tire.

Quick tip: Store your used motor oil in a sealed, leak-proof container and recycle it as soon as possible. Avoid keeping used oil on your property for safety.

DIY vs. Professional motor oil changes

According to a 2023 survey by Canadian Tire, around 70% of vehicle owners prefer professional oil changes, while the other 30% like taking the DIY route. Needless to say, changing your engine oil yourself instead of taking it to an auto boy shop is a great way to save money. But, is it worth getting your hands dirty? Here's a breakdown of the pros and cons of both:

DIY oil changes

Below, we evaluate the advantages and trade-offs of DIY oil-change service:

Pros

• Lower cost: You’ll spend about $40 to $60 on the oil, the filter, and a drain pan.

• Flexibility: No need to book an appointment.

Cons

• Time-consuming: Changing the oil in your car can take anywhere between 30 to 60 minutes or longer, especially if you've never done so before.

• Tools required: You’ll need a a car jack, wrench, gloves, funnel, and other tools that you may not have around the house.

• Messy and risky: If it's your first time, you can spill oil and cause damage to your engine if not done correctly.

Professional oil changes

The following presents the benefits and limitations of professional oil changes:

Pros

• Speed: Most auto body shops can change your oil in less than 30 minutes.

• Expertise: Technicians check other parts of your car are working correctly.

• Convenience: You're not responsible for the cleanup and you don't have to dispose of the oil.

Cons

• Higher cost: Expect to pay anywhere between $70 to $150 depending on your vehicle and they type of oil you need.

• Scheduling: You’ll need to book ahead of time and possibly wait for your appointment.

Can I switch from regular oil to synthetic motor oil?

Yes, you can change from conventional oil to synthetic motor oil. Using a synthetic oil requires less oil changes and better protection against high and low temperatures, making it ideal for Canada's shifting climate year-round. The only downside to using a synthetic oil is that it can be more expensive to purchase.

What happens if I overfill my oil?

Overfilling your oil can lead to "foaming," which reduces your oils ability to lubricate moving parts, leading to engine damage. If you believe you've overfilled your oil, test your dipstick and drain some of the excess.

What does 5W-30 mean?

5W-30 is a common oil type suitable for most climates across Canada. The number “5” tells yo how the oil flows at cold temperatures, while the “W” stands for winter. In this case the "30" references the oils viscosity.

How BrokerLink can help

Regular oil changes are one of the most cost-effective ways to extend the life of your vehicle and maintain a greater fuel economy. The experienced brokers from BrokerLink are here to help ensure you maintain your vehicle correctly, and that includes protecting your investment when behind the wheel. No matter what type of car insurance you’re looking for, you can trust BrokerLink to find an affordable policy that fits your needs and budget including:

• Liability car insurance

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To speak with a broker, contact us directly over the phone or via email. You can also get a free, competitive insurance quote using our online quote tool!

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