Is Synthetic Motor Oil Better for Your Car?

Leave a Comment - 59


Rick Kokan

Subject: oil

I just purchased a 2006 Ford Ranger 4x4 with 56,000 miles on it. In checking the oil, the oil looks black. I asked the dealer about that, and he said they just changed the oil and it is black because they use a synthetic oil. I have always used regular 10w30 oil, and I still have a 1994 Ford Ranger with 258,000 miles on it, the oil looks light brown, it only has a 1000 miles on that oil. I wonder if I am being lied to or should I get another oil change and see how the oil looks, after another oil change

Nelson L. Kieffer

Subject: black oil

Rick, you are being lied to. I use nothing but synthetic and after 25,000 miles the oil is still golden brown, never black.

Jay Racer

Subject: Oil change

Dealer is lying just like ALL politicians. Oil is black because it has not been changed. Trust your experience.

Gary Mc Gurk

Subject: Syn. Oils

I commuted 114 miles a day in TX heat for 25 years. That is a lot of cars and a lot of miles. I used primarily Amsoil. Engine trans and rear end. Occasional Pensoil synth. Changed the Amsoil at 20K or when it got a QT low. Pensoil about 10K. I would buy an inexpensive plane Jane 4cyl stick shift low mileage, Tried to stay with makes that had good reputations and the bigger engines of those makes SI models in Hondas the overhead cam one in Saturns.. Changed everything to synth. I drove them a min of 200K one Honda 297K.Never had any mech. problems on anything lubed except a Dodge Stealth ( hand me Down from wife) that broke a timing belt water pump froze ate the valves.. Every other one still ran great used no oil. I just gave them, away paint faded int was falling apart etc.Or I was just tired of them.
Daughter given a Saturn at 220k she switched to regular oil, at 250 k it threw a rod.
Have a 2002 Dodge Ram with the infamous sludging 4.7 has pulled a 4k lb. camper on vacation in Aug over the Rockies UP the west coast to Portland and back 3 times. mostly in 100 f heat. Never had a wrench on it except for regular maint. Has 147k on it now. runs as good as the day I bought it. Synth. Amsoil engine, auto trans and rear end. I do change that one at 10 K or less if I am towing in the summer.
I am a believer, No I do not baby anything commutes were mostly at 75 MPH + In TX heat. I guess this is about as good a reality test as you can get? Use Synthetic everything choose you own favorite brand change it at max. mileage of your owner manual and rest assured you have a lot of trouble free miles ahead.


Subject: oil

People have those kind of stories using walmart tech oil. All you have to do is change the oil on time. My Toyota 2.l truck got 30 miles a gallon every fill up for 18 years and I mistreated that truck by flooring it on a cold engine after work everyday.
I made sure I changed the oil every 3 thousand miles with wally oil. I sold it at 190k and it finally blew the head gasket at 240k. Replaced by new owner and still running.


Subject: Dexos vs Pennzoil full synthentic

I have a 2011 gmc, been using full syc. My wife has a 2015 gmc and being a new vehicle, gm offers free oil changes for 24K miles.
I took vehicle in to for the oil change and asked what were they using for oil. They pointed to the AC Delco Dexos label and told me it was a BLEND syc oil. So I guess I have been overpaying , using full syn oil as I change myself and dispose of properly.
I selected the full syn oil based upon the GM spec number 4781 . I also see this number in the 2015 manual . I am getting older now and its more difficult to drag out floor jacks and preform the task I have done for 50+ years.
I am now focusing on a Kendall oil change using their full syn oil ,.
Don't like brand jumping but do you have a suggestion? Full syn or blend?
Thank you

Hank Leslie

Subject: oil change

have a 2013 Hyundai Elantra my dealer book recommends changing oil every 7500 miles. Changed it oil and said I should change it every 3000 miles.


Subject: Well OK, but...

does this synthetic stuff taste any better than that conventional crap? I mean that's really all we need to know!

Scott Cyphert

Subject: Oil

I have a 2002 Alero. It has over 166,000 miles to it. Ive been using synthetic blend oil in it. Ive been debating on wether to go full synthetic on it. Any suggetions?


Subject: I purchased a 2001 oldsmobile

I purchased a 2001 oldsmobile alero at 130k miles on it using nothing but full synthetic oil. I drove it until 260k miles on it with no engine problems at all. I ended selling it after I got a new car. I will never go back to conventional oil because I can always tell a difference when I would use conventional vs synthetic. My car rides are alot more smooth with synthetic in my perspective.


Subject: The best way is just pull the

The best way is just pull the dip stick out and simply take a look at the oil,touch and fill it w/your fingers. Bc most of the time after 3-5k miles late,synthetic or conventional will look pretty nasty or not! You be the judge, simple as that. For me, personally I would not trust any type of oil in my engine longer than 5k, bottom line!!!! Whether the oil is still good or not, I don't really care!!! People getting trip out on oil changes these days, when motor oil is your cars blood and is dirt cheap to change compare to getting a new engine. Make no sense at at to me…...


Subject: safe than sorry

I'm with why chance it?I'm lucky in that I work for a retail company and get a discount.I can change my oil for about 23 dollars after discount,That's full synthetic.Why would I chance it after 5000 miles over 23 dollars?


Subject: As a jet engine mech in the

As a jet engine mech in the Marine Corps, at various air bases in California, Japan and Viet Nam, I am witness to the fact that combat jets use only synthetic oil.

Therefore, as an on the road inspector I refused to use anything but synthetic oil. 300-500 thousand miles on an engine can be expected, in my experience. Little 4 cylinder engines need all the help they can get compared to the old 8 cylinder power plants.

Gas mileage with the thinner oil, creating less friction, and saving wear with cold starts and drive aways, and in general, is improved.

An automobile being driven all day can fly past any oil change point. But so can one used only to and from work. Therefore, the knowledge that time between changes is vastly extended can be an engine saver. I have known idiots who boo hoo oil changes at all are.....well.....idiots.

And once you begin using synthetic oil (Mobil One) one must never suddenly switch back to conventional oil.

Ron Allen

Subject: reply

I have 8,000 miles on my Corolla since last change with Mobil1 and respectfully disagree. It still looks like new. Filter is important, cheap filters are just that.

eugene mazzola

Subject: Synthetic vs conventionat

I lease a 2014 Nissan altima and switched to synthetic just to have less time between oil changes. I drive aprox 1000 miles a month. The dealer said oil should be changed every four (4) months. Guess I wasted my monthly...

Nelson L. Kieffer

Subject: every four months

Eugene, I use AMSOIL synthetic 5W30 and change oil every 25,000 miles or one year, whichever comes first. I drive a 2004 Tacoma with 150,000 miles on it with never a problem. It runs just as strong and quit as it did brand new.

Arthur smith

Subject: Oil and filter with tire rotation

My local gas station gives me a oil and filter change uses Wolfs Head oil with tire rotation for a flat $24.00 and brings my car back to my yard when done. I do it every 3,000. Toyota camry V6 xle 118,000 miles and runs new.

D. Black

Subject: Filtration: The Trouble Area With Engines

Full Flow filters all have a check valve. When it opens, all contaminates previously caught by the filter can flush back in the engine through that open check valve. That check valve is required because we do not want to starve the engine of oil during critical moments of acceleration or cold starts. In short, full flow filters are culprits in and of themselves because of that darn check valve. So... Synthetics or Crude Oil is almost a mute point!
Here's the main point:
>We are constantly contaminating engine oil.
>Full Flow filters can flush trapped contaminates back into the main oil supply.
>Changing oil frequently removes contaminates from the oil supply.

We always add secondary oil filtration to our long-term autos. Bypass filters offer serious oil filtration and can lengthen the oil change intervals.

Joel Menschel

Subject: H2 Hummer

This might sound unbelievable but my 2006 H2 Hummer has only 16000 miles on it. With the low amount of driving I do, when should I have the oil changed? I was told not to put synthetic oil in the enging until I have 10,000 miles. I still use regular oil 5W30. This is what the manual calls for. Should I change to synthetic oil and have the oil changed every two (2) years?

Nelson L. Kieffer

Subject: H2 Hummer

Joel, you should have already changed to synthetic. The first oil change removes all the fine metal particles from manufacturing. You go ahead and change to synthetic, and continue to use 5W30 and change it every year.


Subject: time is an issue

Oils (both synthetic and standard are equal in this regard) have additives that are time released. Once they interact with the little bit of fuel, exhaust and other particles that get into the engine the timer is started. If you want to go 2 years without doing an oil change you need to buy oil additive. The additives are pretty cheap. If your mileage is low enough I believe this will be fine. At the same time, do NOT overfill your engine oil. If you put a couple of those bottles in and the engine oil gets overfilled you will be damaging your engine. Literally a quart overfilled is way worse then 2 quarts under filled. If the car manual does not say to wait to put synthetic in then do what you want. There are two schools of engine break in (which some manufactures pre-run/break in engines in the factory). The first school is drive it a like a baby and break it in nice and easy. The other school is break it in the way you want to drive it/treat it. I say break it in the way you want to use it. That way the wear pattern set is consistent. But admittedly I'm much harder on my vehicles then most (not that I have ever seen a premature failure with my vehicles). .... When you get into technical engine break-in procedures it gets really impossible, camshafts want one RPM for break in, cranks another, valves a whole range of RPMs. There is no winning. Good luck.

Roger Coke

Subject: Synthetic motor oil

I would advise anyone NOT to use synthetic motor oil in your lawn mower or any other small air-cooled engine application! I was warned about it by the person from whom I bought a small engine for my lawn tractor but I assumed the other person put it in when the unit was new, and not broken in. I changed to it in an engine that had about 150 hours on it that was not using much between changes and immediately had a problem with smoking and oil consumption! Changing back to conventional oil did not correct the problem. I have not torn the engine down yet, so I don't know what problem it may have caused. Just a word to the wise: I should have listened!

Robert L. Mead

Subject: Amsoil Synthetic Oil

My '92 Chevy PU has been on Synthetic Oil since 8000 miles. The engine runs as smoothly as when new, maybe better. I also have Amsoil Synthetic Transmission Fluid in the Trans. Trans. began shifting roughly so I went to my Dealer and he flushed the system and installed the Synthetic. Within 20 miles of traveling I could tell the difference. As promised the Synthetic clearly cleaned the Transmission valves and smoothed the performance thereof.

Brian Frobisher

Subject: Synthetic Oil

So you asked a bunch of people who make money changing oil and they say it's worth it.
I agree that good synthetic oil is better than conventional oil in that it can take more abuse under extreme conditions and can stand up better to abuse under adverse conditions...
But, under most circumstances the average consumer will not see any advantage over conventional oils with regular oil changes.

If you read the studies done on motor oils, there is little difference between them if they meet certain API requirements, if you change your oil every 3k miles then you can use anything as long as it is the proper viscosity for your engine.

Most experts agree that 3k mile oil changes are a big waste and you probably should drive your oil many more miles up into the 7k range if all you are doing is normal driving.

Changing synthetics at short intervals is a big waste of $$$

Why are some manufacturers requiring synthetic? It's so they can offer you 3 years of free maintenance on the new car, the push the oil change intervals out to 15 or 18k miles and guess how many oil changes they have to perform.....

I don't see how they can "require" you to use synthetic as you can get standard motor oils that meet all the specs of synthetics....sounds like a $$ making scheme to me.


Subject: Synthetic Oil

Brian has a good point, even if it isn't thinking the thought through to the end. Let me explain...
Reducing frequency of your oil change, costs the car owner much less money over time. It also saves landfills by reducing the oil dumped (for people who dump oil illegally); it also reduces the oil waste (for people who dispose of it properly). Synthetic oil has been proven to do a better job over an over again. Here is something people forget: Many synthetic oils allow for better cold weather starts because there is no wax in your oil to thicken up when the weather gets cold, as well as cooling your engine better. Also... many people WILL see a difference in gas mileage OR power after changing to synthetic. There are even synthetic oils specially designed for late model cars.
Let me think...
-Cheaper over time...
-Better for your car (proven over & over, even Brian agrees)...
-Saves oil being dumped (legally or not)...
-Less work for me or my mechanic...
-I could go on but, I switched to AMSOIL Synthetic Motor Oil a long time ago and cannot imagine going backward & using Petroleum again (both my cars, lawnmower, motorcycle, even my compressor for my nail guns).


Subject: Some errors in this piece

First off, both natural and synthetic oils should be good for 5000-7000 miles, not just 3000 miles. However, synthetic oils will NOT last longer for the simple reason that "oil" doesn't "wear out" at all (this is why it is able to be recycled and reused). What wears out is the "additive package" in the oil and that package is roughly the same whether your oil is synthetic or non-synthetic. So buy synthetic oil if you want the best oil available (slicker, better shear strength) and are willing to pay more for it but do not do so expecting to keep the oil in there a lot longer. That is faulty logic.


Subject: article leaves out a lot of information

This article contains some correct information but there is a lot of important information missing. First off, many mechanics are now recommending that higher mile vehicles NOT switch to synthetic, as it often results in new oil leaks. Secondly, some types of vehicles are harder on oil and therefore benefit more from synthetics. These include turbocharged cars that use oil to cool the hot turbocharger bearings, as well as diesels, especially those like fords that use high pressure oil injection to fire the fuel injectors. Vehicles that are routinely subjected to high rpm or high load service will also benefit more. However, as far as the longer oil change interval is concerned, changing to synthetic oil won't reduce the contaminate load of the oil, nor will it help the oil filtration system filter the oil any more efficiently. The only real way to extend oil change intervals is to send oil away for an analysis to determine if your oil change interval can be safely extended. For the relatively small amount of oil most modern engines require, the hassle and cost of oil analysis probably isn't worth it, especially with the average car owner only owning their vehicle a few years from new.

Another thing worth mentioning is that if you have run conventional oil in your engine and build up sludge deposits, switching to synthetic can flush these deposits out. I've read that some people now recommend doubling up on a filter change not longer after switching to synthetic to try and keep a clean filter in there. If the filter gets plugged, more oil bypasses the filter on most vehicles, and this means less oil gets filtered.


Subject: "changing to synthetic oil

"changing to synthetic oil won't reduce the contaminate load of the oil"

So true. Contaminate load is a factor of engine wear and usage. Some oil contaminates can be filtered and some cannot. Thus, oil changes are for those that cannot be filtered.


Subject: Actually, Andrew, SOME

Actually, Andrew, SOME synthetic oils (AMSOIL, for example) does "...reduce the contaminate load of the oil,". A better Synthetic oil surrounds the contaminants & also keeps the metal parts of the engine from touching, better than petroleum oil does. This does a lot to help the engine keep from wearing out. This means your engine lasts longer. This synthetic also helps lubricate your engines seals better, so they don't wear out & let your oil 'leak'.
Many of the stories told in the past about changing to synthetics ruining your engine no longer apply. There is a matter of doing things right though. If you are considering changing over to a synthetic oil, please check with someone who really knows what they are talking about, and not just someone who has a strong opinion. Many people who deal with synthetic oils have had an education beyond that of many mechanics who actually change oil for a living. Many of us literally go to University & learn about engine lubrication, Oil history, etc. So, please be careful who you listen to about such matters. -Thank you.

Russell Peterson

Subject: A synthetic oil change shouldn't cost twice as much!

Regular oil currently sells for around $4 a quart and synthetic oil is around $6 a quart. The cost of the oil filter and the cost of the labor are exactly the same. A complete oil change for most vehicles requires a maximum of 5 quarts. When you do the math, a synthetic oil change should only cost about $10 more than a regular oil change. I see places that charge $30 for a regular oil change and $70 for a synthetic one. If that's the case where you get your oil changed, I recommend that you either do it yourself or find a shop that will let you buy your own oil and filter and only charge you the cost of the labor.

Dick Smith

Subject: Oil change intervals

The 7500 interval between oil changes may be common but it's not across the board. I drive a turbocharged Subaru, Subaru requires synthetic oil for their turbocharged vehicles with a 3750 mile interval change. You can go with a longer interval but unlike Jiffy Lube trying to tell me I need to change my oil every 3000 miles I tend to put a bit more stock in my manufacturer's recommendations.


Subject: regular vs synthetic

I have been told that once you use synthetic you can never use regular again without hurting the engine, is this true?


Subject: No, it is NOT true at all.

No, it is NOT true at all. If your vehicle does not specify only synthetic oil, you can switch back anytime to regular oil but I would not keep switching back and forth numerous times or anything.

Mike Murray

Subject: Synthetic Oil

I worked for a large oil company and handled some of the tax issues related to synthetic oil. Our company claimed the lineage of the discovery of high quality lubrication oil back in the 1860's when kerosene was distilled in a vacuum.

My understanding is that synthetic oil has always been crude oil based. At the refinery an elaborate process is undertaken to reform the hydrocarbon molecules whereby they will lubricate the best. These reformed molecules don't oxidize like simple hydrocarbon molecules which made up a large portion of each can of oil. Synthetic oil can handle the heat much better and also stay liquid at very cold temperatures. When regular oil oxidizes it forms sludge, acid, and adheres to the inside of the engine. If you heat synthetic oil in a frying pan it does not burn and carbonize like convention oil, but rather appears to vaporize. When the synthetic oil was introduced to the retail public it said on the can that it was good for 20,000 miles. Nobody believed that statement because Arnold Palmer had convinced us to change oil every 3,000 miles like he did with his tractor. Actually, the synthetic was probably good for 100,000 miles, but who would believe that?

Here is a tidbit about this oil that few people know. Synthetic oil should technically be called synthesized oil. It was called synthetic oil by our company at the time in an attempt to have this oil exempted from the excise tax -now repealed- which applied to every gallon of oil. There was a tax on every kind of natural oil including cadavor oil. The thought was if it was a "synthetic oil" it would not be subject to the excise tax. The case was lost in appeals with the IRS/Treasury Department for the tax exemption, but the term "synthetic" stuck.

All motor oils have improved in quality, but I feel the synthetic oil is a very wise investment for your car's engine.


Subject: Synthetic oil

Sorry Mike but not all synthetic oil come from dino juice. For example Amsoil make synthetic oil base on natural gas and I`m not sure but Mobil 1 oils are from natural gaz too . Mobil sued Castrol on synthetic oil defenition Castroll oil are effectively based on dino juice and Mobil sued Castroll cause they used synthetics name on oil based on crude oil. Castroll won the case.


Subject: Oil Changes

It is always recimended to read your vehicle manual. Most vehicles are open to how the vehicle is driven. In town day to day driving or driving in unusual weather conditions like extrme temperatures and towing require more frequent oil changes at the recommended 3000 miles. If you drive mostly on the freeway, then the oil changes can be extended to 5000- 6000 miles. I agree that synthetic oil is a premium and usually extends the change time interval to 7500 miles. There have bee a lot of studies, but for sure while the vehicle is in warranty use the suggested grade and change it as recommended otherwise the warranty is void. I listen to Click and Clack on NPR and they feel the same as I have expressed above. I have had multiple vehiclles with 200,000+ miles and no engine problems using the above recomendations. If you are astute pull the dip stick out and look at it regularly. With a clear color and no gas smell you are doing well.If the oil is black or milky and down a quart get in and get an oil change immediately . After 150,000 miles on a vehicle you amy want to go to a long long engine wear type of oil. If the engine makes a lot of noise or the oil light flickers get help, you are looking at a possible problem. I hope this helps someone.

David A. Bess

Subject: Reply to Bill

Hey Bill, you need to check out AMSOIL. The Signature Series Oils are warranted for 25,000 miles or 1 year, which-ever comes first. Also, manufacturers can not void car warranties based on brand of Oil or Drain intervals/Changes.


Subject: Sorry Bill, not exactly correct

Bill said "...but for sure while the vehicle is in warranty use the suggested grade and change it as recommended otherwise the warranty is void." People who own cars & are told stuff like this, really need to read the "Magnuson–Moss Warranty Act". This will also give you information that will educate you beyond what your car dealer or some mechanics want you to know. A car manufacture cannot tell you what oil you have to use in your car (which grade is fine), unless they want to provide that oil for you free of charge. Some of the better synthetics actually last longer than 7500 miles & have been proven to do so many times over.
Don't be mis-informed!


Subject: oil change

Patricia, NO! I use 100% synthetic and change my oil every year or 25,000 miles, whichever comes first.


Subject: No Way!!!

your synth oil is good to go for at least 7500 miles! don't let them gouge you.

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Hi, i worked in the automoble field for 8 years, I was the CIO of a large 8 location dealer group.


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If it is the original timing belt, then yes - check your owners manual for the recommended changing frequency, but from a quick web search (not knowing your exact engine model) it looks like 60,000 recommended internal, and typically last 80-100,000 miles to failure if not changed.

The most frequent comment (and a red note items on manufacturer's website) is that you probably have a "zero-clearance" engine, an idiotic design that means if the valves are not fully closed when the piston come to the top, it hits the valves and breaks or bends them or punches a hole in the top of the piston. Talk about planned obsolescence !

In short, if that is the case and your belt breaks or gets so loose it strips the "teth" off it or slips, your valve timing will be off, and could cause catastrophic engine damage that would require a complete engine overhaul or replacement !

Unfortunately, after looking at a video on how to change the belt, they build it so almost all the auxiliary equipment has to be taken off to change the belt - the alternator, water pump, radiator upper hose, power steering pump, air conditioner, etc - so rough cost is $800-1200 ! If you are getting it changed, it is also recommended to replace the water pump while it is off.

Hopefully some Montero mechanic will hop on this question and expand on this, but NO engine belt of any type should be trusted to go 115K miles.

A great deal depends on the use of the vehicle.  If you do a lot of mountain driving or heave towing, then a flush would be necessary.  Under normal driving conditions, a flush is NOT necessary at 46K miles.  The shops make money on flushes, that's why they recommend them.  Most transmissions are good for 100,000 miles before requiring maintenance.  Your owners manual should say.....if not then leave it alone.  Maintenance is debated between a flush and a fluid drain and fill.  Both have merits and down sides.  Alternative Car Care is not a fan of flushes and will not do them.  We would rather drain the fluid and change the filter.

Assuming automatic transmission:

At a quick lube type place, with unknown brand of fluid - from about $30-60 depending if done as part of a general fluid change package or all by itself. If transmission fluid filters need replacing too (usually are changed with fluid change on an automatic transmission), more like $75-125 range.

At dealer, using OEM parts and fluid, about twice to triple that. Normal auto repair shop about halfway in between those two. One reason for higher price is they will not (if reputable) extract the old fluid through the dipstick tube and put in new - they will remove the pan or maintenance panel (which commonly has to be done fgor filter replacements) and clean the pan at a minimum regardless.

This assumes you do not need band or continuously variable shift friction surface replacement or adjustment, which can crank it up from $50-100 for band adjustment to several hundreds more for replacements.

Do NOT let some shop convince you to pay for a transmission flush - not only is it unnecessary, but usually uses contaminated fluid from other cars or harmful chemicals (sometimes even tap water or diesel fluid) and can seriously damage your transmission. If your transmission filters were not doing their job or you smoked your transmission fluid, the proper cure (assuming not bad enough to require transmission overhaul) is to change to new fluid and filters, then replace them again in a short time - typcially 50-250 miles recommended by manufacturers, to let the new fluid pick up the dirt and sludge and transport to the filters for cleaning.

IF manual transmission - from about $40-75 for one with drain pan and no filters, to as much as $200 range for one with filters that requires removing side panel to change filter and clean it out. Again, higher end at dealers.

My recommendation - ALWAYS require OEM fluids be used for all but engine oil - mixing brands and additives in equipment is just not a good idea, as they can react with each other and cause serious degradation of the lubricating properties, and even cause gel or sludge in the fluid. A transmission, transfer case, differential, etc should be able to run at least several hundred thousand miles without maintenance if you change the fluid as recommended and use only the same OEM fluids in it. The small amount you will save using cheap fluids is not worth the mega bucks to repair or replace a damaged unit. If you go to an auto shop, find out your required refill quantities and buy the fluids at the dealer and tell them to refill with those - just be sure to get enough to allow for a bit of spillage.