conventional vs. synthetic oil

Conventional Oil vs Synthetic
---Thought you all might wanna read this.

Found on searchwarp.com:
One central argument between car enthusiasts and on Internet car forums alike is what oil is better for your car, synthetic or conventional. Before synthetic oils became available for regular automobiles, the argument centered solely on brand types and weight. But now, with the advent of these synthetics all over the market, what is truly the best choice for your engine? Let’s explore both of these worlds to find out.

Conventional oil is rated according to a SAE system. This scale is used so that you know what type of oil is best for your car given the environmental conditions (temperature, city driving, etc.) of where you live. The first number, for example on 10W30 motor oil, is 10 followed by a “W". This “W" indicates that the number before it is the viscosity rating of the oil. The lower this number, the better the oil is for colder climates. The higher the number, the better it is for hotter driving conditions.

Synthetic oils, on the other hand (before their commercial release) were used in many military vehicles and fighter jets. Airlines also use synthetics in their engines. The synthetic oil has been designed not to break down as quickly and can tolerate extremities in temperature and weather (hot to cold).

One of the major differences between conventional and synthetic oils is that synthetics are treated with more additives that protect your engine for a longer amount of time before you have to change it. And, while we don’t want to get into all the molecular chemistry involved in the making of these oils, we should mention that they also last longer in hotter conditions and won’t “gel" in colder ones, like conventional oil. In other words, synthetics have more additives, which greatly protect the car from viscosity breakdown. They are designed to withstand temperature extremes. It may be safe to say that extreme driving conditions call for the use of synthetics.

On the financial side of the matter, synthetics cost a whole lot more up to three or four times as much as regular conventional oil. But, the wonderful thing is that you don’t have to change your oil every 3,000 miles recommended with conventional oil use. In fact, you may not have to change it until well after 25,000 and up to 50,000 miles as long as the oil filter is changed every 10,000 miles. So, the cost at first might scare consumers away, but the long-term benefits of synthetic oil use are substantial.

However, you will still have to be responsible for your car’s maintenance check-up every 3,000 miles or so. With regular oil-changes, you are automatically checking over the car for other problems (or if you don’t an inspection mechanic does). It might help you find a problem that could be dealt with, that could’ve gone unchecked. Also, you’ll want to check the synthetic oil every now and then to be sure that it isn’t contaminated and/or that there isn’t any moisture build-up.

With normal everyday driving, perhaps conventional oils work best for you. You aren’t driving in extreme conditions and you swear allegiance to regular oil. That may be fine. Synthetic oil cannot really offer you anything that conventional oil cannot under normal operating conditions. However, the definition of extreme driving states that if you do a lot of short driving (two to twenty miles) daily, it’s hard on your car. And, specialists agree that this constitutes extreme driving due to the faster breakdown of the structure of conventional oil.

Another major reason that many are choosing the synthetic route is that it contains fewer impurities impurities that can cause your engine harm, perhaps to the point of premature engine wear. With conventional oil, there’s no way to totally rid, filter or clean the impurities from the natural elements. That’s another reason why synthetic oils do not have to be changed as much even in extreme driving conditions.

You’ll want to be careful however, if you do decide that you want to give synthetic oils a try. If you’ve been driving your 1983 Ford Thunderbird for years using 10W30, you may not want to switch using your conventional oil brand.

Conventional oils have solvents that stick to gaskets and seals and often cause them to swell a certain way. These gaskets and seals have been used to the same oil for years and the switch to any other type of oil (whether it is to a different conventional oil brand, or an upgrade to a synthetic) may be harmful. The oil you change (or upgrade to) will also have solvents and additives, different from the original. So in other terms, the changing of oils could result in oil leaks and/or a once small oil leak becoming bigger due to the reaction the seals and gaskets will have to the change (not because of the oil itself). If you think that this might be the case for you (i.e. if you have an older car using conventional oil), it’s recommended that you not try synthetic oil until you have an engine (or new car) with relatively virgin gaskets and seals that will be able to acclimate much more easily to the chemical changes of the newer type of oil.

It’s easy to see that that fanfare for one or the other is an argument that has really been explored. It’s best for you to decide what will fit your personal needs. If you have an older car, you may want to wait until you upgrade. However, if you have a newer car, the benefits of synthetic oils are easily seen. Again, it’s solely dependent upon you and the conditions where you drive. Synthetics are shown to provide their best protection above 250 degrees Fahrenheit. Most people do not drive their cars this hot. However, many do drive in cities, where driving times are considered to be more of a “stop-and-go" nature, which may be considered “extreme" in many circumstances. When the time comes for you to make a decision, at least you’ll be informed of the differences of each. And, until that time, no matter what, keep up that automotive pride!

Michael Walker is a freelance author providing tips and hints on engine related topics such as JDM motors, used import engines and engine swaps. His articles are a valuable source of information for the auto enthusiast.


More info found on Castrol.com:
Looking for the real story on synthetics? Wondering what's true and what's not? These are some misconceptions about synthetics, and facts to set the record straight:
MYTH: Once I use synthetic motor oil in my car, I cannot switch back to conventional motor oil.
FACT: Synthetic motor oils are compatible with conventional and part synthetic (blend) motor oils. However, synthetics deliver superior engine protection versus conventional oils.


MYTH: Using synthetic motor oil will void my vehicle’s warranty.
FACT: Using synthetic motor oil will not void your vehicle’s warranty. Synthetics are formulated to not only meet minimum required industry standards, but also, in many cases, meet tougher industry and vehicle manufacturer standards.


MYTH: Synthetic oil is only for new cars.
FACT: Quality synthetic motor oil can be used in old as well as new cars, including vehicles in which conventional oil was previously used. Synthetic motor oils are beneficial for the good health, long life and top performance of new and old cars.


MYTH: You need to allow a break-in period for new vehicles before using synthetic motor oil.
FACT: In the past, it was recommended that conventional motor oil be used for your first oil change to allow for some controlled wear to break-in the new engine. However, with current engine technology, a break-in period is not necessary. You can use synthetics immediately.

Info found on aircooled.net:
Synthetic Oil Explained

Whether it's evil stuff or good stuff depends on who you talk to. And a lot of what you hear from backyard mechanics is rumor and myth. Myth # 1 is the claim that you don't have to change Synthetic oil as often as regular motor oil. Remember when Mobil 1 said you could go 25,000 miles between oil changes with synthetic oil? Notice they haven't said that for a good number of years? Keep that thought on the back burner for now... Myth #2 is that synthetic oil causes oil leaks. In this article I'm going to try to dispell these myths for you with the cold hard facts about the differences and similarities between dino vs. synthetic oil.

Let's talk first about what "dino" oil is (Dino is short for Dinosaur, which is when it started forming). Dino oil is created from something called "Base Stock". Base stock what the oil companies get after they have processed the crude oil that comes from the ground. From there, additives are combined with the Base Stock, to create our motor oil. There are 7 main additives which include anti-foaming agents, anti-corrosion, etc, etc. At the molecular level, dino oil contains molecules of varying sizes. Imagine the floor of a gymnasium covered with basketballs, baseballs, volleyballs, and beach balls. Now imagine that all those different size "balls" are moving around, flowing past the floor. Every time a ball surface contacts the floor surface, the ball absorbs heat from the floor. That is how oil removes heat from your engine components, from surface to surface contact.

Now imagine the same gymnasium floor covered in uniformly sized golf balls. Smaller, more uniform molecules can absorb more heat from a surface, because there are more of them AND they have a larger surface to volume ratio which means they have more surface area contact. That's what synthetic oil is. A man-made "Base Stock", where all the molecules are the same size, and smaller than those in dino oil. Better heat transfer, better lubricating properties, and a lot wider temperature range without breakdown, are now obtained.

Myth #1 debunked

Oil does not break down under normal use. This is true of both dino and synth oil and is also the reason why you take oil to the Recycling Center and not the trash dump. So if oil itself doesn't ever degrade, why do we have to change it? The answer is twofold: additives and contamination. It will probably surprise you to learn that synthetic oil has all the same additives that dino oil has! The additives in oil DO break down, which is part of what necessitates oil changes. The other reason for regular oil changes is that with use, motor oil becomes contaminated (dirt, water, acids, etc). Using synthetic oil does not protect against either of these problems, which is why you CANNOT go further between oil changes when running a synthetic. You should still change your synthetic oil at the same intervals as you do with dino oil. Anyone want to guess how many claims Mobil 1 had to pay to people that were going 25,000 miles between changes?

Myth #2 debunked

Synthetic oil causing oil leaks is another commonly spread myth. The truth of the matter is that if all your engine seals and gaskets are in good condition, synthetic oil will NOT leak in your engine. The myth started because on occasion, an engine will leak with synthetic oil, but not dino oil. The reason for this is that the smaller molecules of the synthetic are able to get past very small crevices, where the larger molecules of dino oil cannot. But this does not mean that the synthetic oil has caused the leak, it simply has "discovered" an infant leak, and regardless of what oil you are running, this infant leak will eventually grow to a size that will allow dino oil to occupy and pass also. Synthetic oil has not been shown to deteriorate engine seals or gaskets. It is not some evil solvent that will break down sealant, or anything like that. Like was said earlier, it is just a man-made base stock, that is uniform and smaller in molecule size than dino oil. Nothing more, nothing less.

Found on mobileoil.com:
Myth: Mobil 1 will leak out of the seals of older cars.
Reality: Mobil 1 does not cause leaks. In fact, new Mobil 1 was tested in dozens of industry standard and original equipment manufacturers (OEMs) tests to prove its seal performance. It is fully compatible with the elastomeric materials from which all automotive seals and gaskets are made. If an older engine is in good condition and does not have oil leaks, Mobil 1 provides the same advantages as when used in a new engine. ExxonMobil recommends taking measures to repair the leaks, then using Mobil 1. ExxonMobil also recommends following the automobile manufacturer's manual for the proper oil to use.


Found in the backside of my skull, working hard to make a decision to swap from conv to syn:

There are lots of convincing stores out there for syn and against syn.
I had planned to swap the crx fron conv to syn, but am reconsidering.
I do not believe that syn oil causes leaks, however I do believe that it would seep out more easily from a pre existing problem that may have not yet leaked with conv oil. Being that the molecules are smaller with syn oil, this stands to reason.
If your planning to swap, I hope this helps clear a few things up, and if you've already swapped, post up your story.