Is Synthetic Motor Oil Better For Your Car?

Is synthetic motor oil better than conventional oil?
Thank you to Pennzoil for bringing me out to the 2016 Canadian GP and sponsoring this video! This video has been compensated by GarageMonkey and its advertiser. All opinions are mine alone.

The viscosity of an oil is its resistance to flow. A greater viscosity means more resistance to flow, or a thicker oil. A lower viscosity means a thinner oil.

Before understanding the benefits of synthetic motor oils, like this Pennzoil Platinum derived from natural gas, we first need to understand the rating system used for motor oils. You’ll often hear 5W-30, or 0W-20 as ratings used in cars today. These are multi-grade viscosity oils, meaning their viscosity grade changes with temperature. The first number, followed by a W, is the cold rating (W stands for Winter), and this means the oil behaves like an SAE 5 grade motor oil (using 5W-30 as the example) while cold, but at operating temperature, at about 100 degrees C, it operates like an SAE 30 grade motor oil.

Now 30 is higher than 5, so initially it may seem that the oil would get thicker at higher temperatures, which is obviously not the case. A straight SAE 30 grade oil will be thicker at lower temperatures, as will a 5 grade oil. Even though a 30 weight oil is thicker than a 5 weight oil, at 100C the 30 weight will be thinner than a cold 5 grade oil.

Low viscosity at low temperatures is important, because this is where a significant amount of engine wear occurs, so it’s critical to maximize oil flow to protect the engine. At colder temperatures, thinner oils will flow better and thus offer better protection.

For a conventional oil, for example while creating a 5W-30 oil, you’ll start with a base oil similar to an SAE grade 5 motor oil, and include additives to alter the viscosity rating. To improve low temperature flow, pour point depressants (PPDs) are added. To increase the viscosity at high temperatures, viscosity index improvers (VIIs) are added. VI improvers are polymers which expand in heat, making it more difficult for flow, thus increasing the viscosity.

Synthetic oils, however, can have base oils which are already formulated as a multi-grade oil, meaning you don’t necessarily need additives, or as much additives, to alter the viscosity at different temperatures. The major benefit here is that additives tend to break down over time, so synthetic oils will maintain their original viscosity properties much better throughout the engine oil drain interval versus conventional oils. (Diagram illustrating viscosity vs temperature)
If you were to plot two 5W-30 motor oils, one conventional and one synthetic, at the beginning of the oil change interval, they would have similar viscosity properties. At the end of the interval, however, the synthetic would act nearly identical to the original oil, while the conventional oil would be thicker at low temps, and thinner at high temps.

Now does this mean that with synthetic motor oils you can extend your engine oil drain interval? No! It just means your engine is better protected throughout the engine oil drain interval. There are still additives (anti-wear, dispersants, anti-foam, detergents, rust inhibitors, corrosion inhibitors) which wear out over time, so you should always change at whatever interval your owners manual suggests.

And don't forget to check out my other pages below!

NEW VIDEO EVERY WEDNESDAY!

[SirLoinOfsteak]

I have a VW 2L turbo engine in my car, so I don't need to worry about old oil as VW have thoughtfully made engines that burn through the oil at alarming rates, meaning the oil in my car is never that old! Another innovative feature from the VW group.

[MrCaveman]

I was active duty US Air Force for 24 yrs and retired a few years back but long story short (hopefully) I managed laboratories that tested aircraft engine oils for wear and tear. We used Atomic Emission Mass Fluid Spectrometers to test at the molecular level...normally in PPM or parts per million. We tested about 16 different elements for wear in particular places in any given engine. We started using synthetics many years ago...say early 80's. We kept meticulous records on each serialized engine so we could create and track wear. I can't go into great detail but suffice it to say that we started off testing every flight and then moved to 400 flight hrs, then 800, then 1200, (for oil changes) then only when we had a engine problem. Some places still test every flight hr but synthetic oils proved to be the best as far as wear and tear. I switched all my vehicles to synthetic at their 1st oil change. I would not recommend switching a vehicle to synthetics if it has a lot of wear miles on it because synthetic oils will "slide" around worn parts. Another big plus for synthetics is you can qchange your oil at half or more the rate of conventional so if it's recommended every 3000 miles then it's safe to go to 6 or 7000. In My Opinion! I have been doing this since the mid 1980's and I had the ability to test these same oils for wear. If you spend $30.00 every 6 or 7000 then you'll save at least one oil change plus synthetics wear better, give better lubrication, are not as heat ploblematic as far as heat transfer, and don't break down like conventional oils. Just my 2 cents.

[TheTruthSeeker]

I'm an engineer and its hard for me to learn something new that blows me away and today my friend you totally made me learn something new with the demo. Thanks, Ill be going fully synthetic from now on.

[The_R-n-I_Guy]

I just switched to synthetic oil in my high mileage engine. I can tell the difference by the sound. It runs a lot quieter

[hmdchy]

I felt like I am watching a school lecture.. but at least this one is relevant and beneficial to my life.

[RealDarkFilm]

The manual for my car says to use 10W-40, but Ive found using WD-40 instead runs better at start up

[rackey]

5:34 Here's the part you're here for.

[Tactical.Pastor]

I worked at Jiffy Lube 16 years ago and they never explained this to us. We just knew that Full Synthetic was better than conventional. Thank you for the detailed break down!

[RedesCat]

i use non-stick cooking spray as my motor oil

[towallomeesgel]

This guy should have been the new Spock.

[danielfleming]

Sold motor oils for years. Also conducted hundreds of oil analysis for contaminants and longevity. Two basic rules are: Use a high quality oil. Use a very high quality filter. Typical standard motor oil will last 6000 to 8000 miles in a healthy engine. Synthetic oils will last 12000 to 15000 miles in a healthy engine. If you're ever curious about your particular engine, get an oil analysis kit from your parts store and do your own analysis. You mail a sample of your used oil into a lab, and they send you a report of it's condiiton. Increase the mileage between each change until the analysis shows that the oil is beginning to degrade.

[SupremeTycoon]

WOW! Someone finally explained oil viscosity properly! I've seen your videos before I don't know why I didn't just come to your channel in the first place.

[Pigeonbutter]

I've found ketchup with a bit of mayonnaise mixed in works best with my Miata. It must be that Japanese engineering that requires the extra premium lubricant

[mjc]

6:32 - *_FREEDOM!!!!_*

That took around a minute. Holy crap.

[sarahwu]

it's so clear that you enjoy your work and enjoy explaining things to other people. your explanations are very clear and helpful. keep up the passion and good work.

[voicetube]

I've been watching a few of your videos now and have to say they are EXCELLENT. You are excellent at communicating this data – clear, natural and easy to watch/listen to. Can't say that about all Youtubers – rock on brother!

[NoahKuzel]

so is the answer yes, yes synthetic motor oils are better than conventional?

[BigDaddyJinx]

This is simple science.

Conventional was simply discovered to work with engines after some coaxing.

Synthetic was DESIGNED to work with engines. Specifically engineered to work with them.

I'll gladly pay the premium to get a product that was designed to work as opposed to, "Hey this seems to work!"

[atanngaraj]

As I know, high temperature and low temperature oil grade measurements are observing different characteristics. For high temp ratings, they use kinematic viscosity characteristics, but for cold ratings, they use cranking and pumping viscosity characteristics. I am not an expert, but I' ve searched "Oil" topic for a long time. The data which I mention about can be found in Amsoil website (Straight - Multi grade oil comparison task). This sentence is a copy from there "Obviously, cold temperature or W ratings are tested differently than regular SAE viscosity ratings. Simply put, these tests are done with a different temperature system" Thanks for the video, very useful info.

[DannyZabolotny]

There's really no excuse to be using non-synthetic oil... you can buy 5 quarts of full synthetic Mobil 1 at Walmart for like $25.