Can you switch from full synthetic to synthetic blend

Oil Change

Should You Switch to Synthetic Oil?

• Oct 21,2019

“Would you like synthetic or conventional oil?”

When faced with this question, it might seem easier to choose the cheapest route. Compared to conventional oil, synthetic oil can have a slightly higher price tag. If synthetic motor oil makes a difference in engine performance, though, is it worth spending a little extra? The short answer is, yes. Changing to synthetic oil might be a good idea. Read on to learn why.

Should I switch to synthetic oil?

If your engine is equipped to handle it, switching to synthetic oil can be a smart move. Synthetic oil performs at a wide temperature range and is ideal for engines with direct injection, variable valve timing, turbochargers, or superchargers that operate hotter.

Unfortunately, there are many motor oil myths about switching from regular to synthetic oil that confuse drivers. To demystify synthetic oil, let’s look at the top benefits of switching to synthetic and some common myths.

Synthetic Motor Oil Benefits

• Synthetic oils can withstand colder temperatures than conventional, so you enjoy worry-free startups in freezing weather. (That's one reason changing from regular to synthetic oil in winter can be a good idea!)
• Synthetic oils can also withstand hotter temperatures, which reduces burn-off in the summer.
• Synthetic oils, such can help clean your engine, prevent sludge buildup, and improve fuel economy.
• Synthetic oils have fewer impurities than conventional oils, thereby increasing the overall longevity and performance of your engine. Less sludge means smoother operation from the get-go.

Synthetic Motor Oil Myths

• Switching to synthetic oil causes leaks: Generally, switching to synthetic oil does not cause leaks. It is true that synthetic oil is thinner than conventional oil and therefore flows more easily. If there is a spot where oil could leak out in your engine, then synthetic oil is more likely to leak than conventional. However, synthetic oil would not cause the leak.
• You can't switch back to conventional oil: Once you switch to synthetic, you are not bound to it forever. You can switch back to conventional oil if you choose to do so and your vehicle manufacturer doesn't recommend otherwise. However, continuing to use synthetic oil may help prolong the life of your vehicle by taking better care of your engine.
• You have to break in a new car with conventional oil: Some people might think you have to break in a newer car by using conventional oil for a time before switching to synthetic. In reality, there are no recommendations for this procedure from any vehicle manufacturer. In fact, many new vehicles are now shipped out of the factory with synthetic oil.

How to switch from conventional to synthetic oil

Knowing what makes synthetic oil better than conventional is only the first step. The next step is to make the switch! Talk with your technician and consult your owner's manual. Synthetic oils are not all the same and not all engines are equipped to handle them. In the end, the best motor oil for your vehicle is the one your manufacturer recommends.

At Firestone Complete Auto Care, we trust Pennzoil® Synthetics to keep your engine in top condition. Not only does Pennzoil help your engine run more efficiently, it actively cleans it while you drive. So, if you want a cleaner engine and better peace of mind, stop by your nearest Firestone Complete Auto Care to get a Pennzoil synthetic oil change.

Top

We're going to give it to you straight: Yes, you can safely switch to synthetic oil. But it would probably help to know the details about what we're talking about -- specifically why this question would even come up in the first place. And it does -- a lot.

First off, let's talk about what synthetic oil is. To begin with, there's a base oil that does most of the work of lubricating engine parts. It's lab-created, as opposed to being a product of the refining process of mineral oils that are pumped out of the ground. There are also performance additives (in powder form) in many synthetic oils, and a carrier oil to suspend these additives in the mix.

So what's the practical difference between synthetic oils and mineral oils? There's not much difference when you're just looking at two clean puddles of oil, according to Kevin Chinn, a technical advisor at ExxonMobil. "You'd slip on both of them," he says. But the advantage of synthetic oil is that its molecular structure stays more stable with temperature changes and extends the maintenance interval between oil changes.

So why the heck wouldn't you want to switch from mineral oil to synthetic? Keep reading to find out some of the myths and realities of these high-tech oils.

Myths about Synthetic Oils

The most often cited myth concerning synthetic oil is that it will wear down the seals in your engine and cause leaks. That just isn't true. Well, for the most part, anyway.

Like many myths, this one is based in fact. Early synthetics were made of esters, which were harder on seals, especially those made of neoprene. However, synthetic oils have come a long way since the early 1970s, and they're much nicer to delicate seals. But while synthetic oil won't create a leak, it will find one. Its streamlined molecular structure has no mercy for cracked or otherwise marginal seals. The oil and its additives may even clean deposits from the engine, which is good -- unless those deposits are acting like spackle on questionable seals.

Related to this is the myth that if you started with mineral oil in your car, you can't switch to synthetic oil. As long as your engine's seals are in decent shape, you can switch back and forth to your heart's content. You can mix and match, you can use blended synthetic and mineral oil or you can use mineral oil for 3,000 miles (4,828 kilometers) and synthetic oil for the next 5,000 miles (8,047 kilometers). You could even fill your reservoir with five different oils from five different manufacturers, and as long as they're the same weight, it will do your engine no harm, according to David Canitz, technical services manager at Royal Purple.

So let's consider those popular myths busted and move onto the realities of switching to synthetic oil.

Realities of Switching to Synthetic Oils

Since synthetics are created in a lab and contain additives to keep your engine in tip-top shape, they're more expensive than traditional mineral oils. How much more? Try six to 10 times the price, according to Cantiz at Royal Purple.

However, there are ways to get some of the benefits of synthetics without breaking the bank. For those who live in climates with noticeable seasonal changes, you could use a synthetic oil in the winter months when your engine is under the most stress from cold starts, and then switch to a mineral oil in the summer, when its more random molecular structure will remain warm and easy flowing.

For modern cars, mineral oils are good, blended oils are better and synthetic oils are the best. But if you've got a 30-year old car with original seals, the truth is, no oil or additive is going to help much.

For more information about motor oil and other related topics, follow the links on the next page.

Lots More Information

Related HowStuffWorks Articles

• Engine Performance Quiz
• How to Change Oil
• How Car Engines Work
• How Oil Refining Works
• Why is quality motor oil important?
• What's new in synthetic oil technology?
• Is anyone developing lifetime engine oil?
• What if I never changed the oil in my car?
• Why would I upgrade to a synthetic motor oil?
• What's the difference between gasoline, kerosene, diesel, etc.?

More Great Links

• Royal Purple
• Mobil 1
• Amsoil

Sources

• Canitz, David. Royal Purple Technical Services Manager. Personal Interview. Conducted on Feb. 6, 2009.
• CarBibles.com. "The Engine Oil Bible." (April 27, 2010)http://www.carbibles.com/engineoil_bible.html
• Chinn, Kevin. ExxonMobil Lubricants and Specialties, Global Flagship PVL Technical Advisor. Personal Interview. Conducted on Feb. 11, 2009.