Oil is the lifeblood of your car’s engine. It keeps all its parts moving smoothly, absorbs excess heat, and contains additives that help clean up nasty, harmful chemicals. After spending thousands of miles keeping your engine running right, your used car’s oil degrades and needs to be changed. It is one of the most important maintenance items your vehicle should receive. At the cost of a tank of gas or two, it also happens to be one of the cheapest investments you can make in your vehicle’s long-term health and performance.
When it’s time to change your oil, you may be faced with the decision between conventional motor oil and synthetic motor oil.
Which option is best?
Read below to understand the difference and decide what’s right for you.
What’s the Difference between Regular and Synthetic Oil?
Let’s start with some basics.
Conventional oil is distilled and refined from crude oil, a naturally-occurring liquid fossil fuel. Synthetic oil, on the other hand, is created artificially, molecule-by-molecule, from chemical compounds with the goal of mimicking the best properties of natural oil and tailoring to the specific demands of modern vehicle engines.
While the difference in the manufacturing process is neat for car geeks, most drivers only care about the difference this makes for their vehicle. It turns out, these differences can be meaningful. Synthetic oils generally protect your vehicle better than conventional oils, have some performance advantages particularly in extreme temperatures, and last longer. That said, they also cost more.
Cleanliness & Wear Protection
clean car is a happy car
Oil degrades as it moves through your vehicle’s engine, leaving harmful deposits, and over time can form sludge, which decreases your engine’s performance and useful life. Synthetic oil has fewer impurities and is more resistant to sludge formation, so your engine stays cleaner, operates more efficiently and lasts longer than with conventional oil.
Oil’s primary function is to lubricate engine parts, which move at high speeds and are in direct contact with one another. Synthetic oils don’t break down as easily as conventional oils, so they protect your engine components from friction, wear and tear, and ultimately break down for longer.
What is the best car oil for extreme temperatures?
Because synthetic oil has been painstakingly and mathematically engineered for its purpose, it generally performs better than conventional oil in extreme temperatures, keeping your car running more smoothly in most conditions. Engines generate heat in all conditions just by running, so high heat environments can cause oils to break down even faster. Synthetic oils resist heat better, breaking down more slowly, so your engine will last longer in high temperatures.
In cold temperatures, conventional oils can become thick and take more time to warm up to the ideal viscosity, so they may not provide the proper lubrication when you fire up your engine. Synthetic oils are engineered to flow smoothly in your engine even at cold temperatures, so your engine is more likely to receive the proper protection as soon as you start the car.
How long does car oil last?
Conventional oils break down more quickly so must be replaced more frequently than synthetic oils. If your car takes conventional oil, most mechanics recommend an oil change every 3,000 to 5,000 miles. On the other hand, if you use synthetic oil, you should probably change it every 7,500 miles, though some synthetic oils last 10,000-15,000 miles.
Cost difference for Synthetic vs Regular oil?
Mechanics will typically charge $30-$45 for a conventional oil change. Full synthetic oil changes typically run $70-$100, depending on the vehicle. While full synthetic will cost you 2-3x more per oil change, you also get 2-3x the life between changes, so it’s important to factor in that longevity when comparing the cost.
If you drive your vehicle 12,000 miles per year and change your oil every 3,000 miles or four times per year, you’ll likely spend $120-$180 per year on conventional oil changes annually. Using the same 12,000 miles per year, changing your every 7,500 miles with synthetic oil implies an average of 1.6 oil changes per year, bringing your average annual cost to $112-$160.