Harold57

Can't say I agree with your observations there lugnuts, but here is my take on the subject. Here are some real world experience rather than emotional.

Yes, synthetic oil is better suited for extreme environments (very cold and very hot), but for the majority of us, it really won't make any difference if we change the oil every 3000 miles or so (or so slight that we will never know the difference).

Yes, natural oil will break down over time with use and synthetic oil's break down is very slight, practically enough to say that it doesn't really break down.

I ran a 1984 Dodge Rampage (a little pickup made on a Charger base) with a 2.5 l engine on natural oil for well over 200 kmi over 13 years, gave it away to our assistant pastor who drove it for a year or more, who gave it to his assistant pastor who drove it for at least a year and I lost track of it after that. I never had a problem with the engine.

I've driven a couple of other cars on natural oil well into the high 100 kmi range without engine problems. So I can give you a handful of true life experiences and tests that indicate that using natural oil will not wear out your engine if handled correctly.

Between my wife and I, we've owned over 10 cars (which is probably just a couple of years of ownership for SCDROPTOP) and I've always been diligent about changing the oil every 2500 to 3000 miles. We've never had any trouble with oil related engine problems. (Water pumps, radiators, a/c systems, polution pumps, carburetors, etc, yes, but not oil related engine problems.)

The problem comes when folks skip oil changes and run the natural oil beyond the recommended ranges that's when the oil begins breaking down and the resulting chemicals begin eating at the engine internals.

We don't pull trailers either, so I can't speak to that situation. However, there are probably less than five SC430s around that pull trailers.

tfeni52355

Amsoil 0W-30 Synthetic since owning our 2002 SC.

Here's the reasons:
1) I only change the oil once a year which is about 7500 miles or so.Amsoil will go 17000 miles without changing.
2) The 0W-30 will get to the upper end of the engine sooner than a 5W-30 and since the SC sits for days or a week sometimes I want oil on the metal ASAP.
3) Since I change the oil myself and only have to do it once a year I get the best oil protection possible at a price comparable with others who change their oil every 3000 miles.
4) I also get to keep my time to a minimum (1 hr per year) since I'm not waiting on a service tech. Don't know what your time is worth but mine is incredibly expensive to me......

For a car driven 7500 miles a year:
3 oil changes at $20 per at Jiffy Lube = $60
1 oil change in my garage with Amsoil = $65-$70

I do it for convenience and if the synthetic helps, so be it!

toxic

Ahhhh, the debate continues!! Personally, I use synthetic in the Lexus and my truck. I have a jeep Wrangler with 270,000 miles that has had nothing but regular dino oil and changed very 3,000 miles since day 1. Funny thing is that I am sponsored by a Chevrolet dealer and they put synthetic in it after the first break-in and they want it back every 3,000 miles for new oil. Doesn't cost me a dime so I do it. It's got 100,000 miles on it and no problems. Bottom line, I have run both and have high mileage on both but the synthetic makes ME feel better and that is worth the extra cheddar. Besides, it does no harm and has its own set of benefits.

TOXIC

rdostroph

There's a reason Mercedes and other manufacturers only use synthetic oil. Trust the research. It's worth the cost. As a performance engine builder I've used nothing but synthetic in all my motors. When I made the switch in my wife's Lexus, her freeway mileage went up. I recommend replacing the stock filter every 2500 miles and topping off the oil level, then complete change every 10,000 miles.
Additionally, strongly recommend premium fuel and using an additive cleaner every 5,000 miles to keep injectors operating at top efficiency. They're expensive to replace.
In more than 35 years I've never had an oil related failure in a motor with synthetic.

Swishh

After what happened to me in 95 I am too afraid to ever use synthetic again. I owned a 95 Mazda RX7 and wanted to use synthetic for better heat protection, etc. The day after changing to Mobil 1 fully synthetic my car wouldnt start! I took it to the dealer and found out that I had ZERO compression in the rotary engine. I later learned (the hard way, lol) that synthetic oil in a roraty is bad news because the seals get eaten away from using synthetic. It was new news to me! Luckily the dealer replaced the motor under warranty which cost $11,000 at the time. They made me sign a disclaimer to never use synthetic again or else my warranty would be void. Since then I just use conventional oil and change it religiously every 3k miles.

bacardi

I use Amsoil Oil and Filters with Prem. gas.

Tensi

I have relatively low miles on my SC and am running dino oil but want to swap to synthetics.


1. is there any specific work I need to do in doing the swap from dino to synthetic?

2. I was going with the Lexus recommended 5k or 6 months.. can I really elongate that interval safely?

jzwu

Nothing special to switch to synthetic.

I personally change every 10k miles or one year using mobil 1 5w30. Over 80% of my driving is on freeway.

Jabberwock

For my money, the best source of excellent info and data and links to studies on oil is the BITOG forum. Read and learn.

http://www.bobistheoilguy.com/forums...s.php?ubb=cfrm

My advice to folks posting is that they actually post a link to any independent study they claim supports their view. And posting anecdotal stories about what a neighbor or a local mechanic says is certainly fun to read but isn't all that convincing.

Full disclosure - I did quite a bit of reading/research on the subject and arrived at the conclusion that I would run full synthetic in my LS430 because its a better lubricant and because the price difference just isn't that much if you are smart about it.

kjcole

First, if I kept my vehicles only for a few years before selling/trading I'd stick to conventional oil and 5000 mile change intervals with no worry. Since I tend to keep mine for longer and typically go into the 200kmile range (with the help of wife and kids) I use synthetics (engine oil, differential) in all my vehicles (cars, vans, touring motorcycles). Why? Extended life (fact, not myth) and superior flow at start-up especially in low ambient temps (fact, not myth). The latter is a concern on those below 0F mornings in the upper midwest. I was sold 20 years ago with my 84 Audi 5000 CS Turbo-Quattro listening to (hydraulic) lifter clatter slowly decrease on those frigid startups with conventional oil, compared to nearly instant pressurization of those lifters after switching to a synthetic oil. On one oil change I switched back only to hear the startup clatter return in a few weeks. Synthetic all the time since that experiment.

iolmaster

iTrader: (1)

Just curious?? Please provide independent documentation of your (fact,not myth) Anecdotal evidence is not of any value.

kjcole

Let's not forget that synthetic oils were developed simultaneously in Germany and in the US before and during WWII specifically to obtain lubricants that performed better over wider temperature range, with fewer volatile byproducts etc to reduce deposits, etc. In Germany, however, reduced access to mineral based oil reserves during the war spurred this development by Hermann Zorn.

Here's a quick blurb from Popular Mechanics, even though it is not a peer-reviewed scientific journal:

http://www.popularmechanics.com/cars...oducts/4232672

and a short excerpt from that article by Mike Allen:

"Briefly, there are two types of "synthetic" oils on the market. Group IV oils consist of molecules that are synthesized from simpler chemical compounds. This lets the chemical engineers "tune" the characteristics of a lubricant to exact specifications. These oils flow more freely at extreme low temperatures and don't break down at very high temperatures. As a side benefit, they generally can be specified one or two grades lighter than a mineral oil, which consumes less energy as friction inside the engine and saves fuel."



or, we can go here, in a peer-reviewed scientific journal:

Development and performance advantages of industrial, automotive and aviation synthetic lubricants
D. A. Law1, J. R. Lohuis1, J. Y. Breau2, A. J. Harlow3, M. Rochette4
Journal of Synthetic Lubrication
Volume 1, Issue 1, pages 1–33, April 1984

Abstract
The study and use of some types of syntbetic lubricants can be traced back 50 years.1 Within the past twenty years, rapid advances in technology have resulted in syntbetic lubricants that can operate satisfactorily over temperature extremes well beyond the capabilities of conventional petroleum-based oils. Current emphasis is on the ability of some types of synthetic lubricants to allow more efficient system operation, with concomitant energy savings and extended equipment and oil life. Several definitions have been proposed for synthetic lubricants. In this paper, the authors define a synthetic lubricant as a product which consists of base fluids manufactured by chemical synthesis and containing necessary performance additives. Thus the base fluids are tailored, through specific chemical reactions, to meet predetermined physical and chemical quality targets. In this paper, discussion will be limited to (a) a review of the types of chemicals which have been studied for use in synthetic lubricants and (b) selected application data which dramatise some of the advantages gained through use of the synthetic lubricant.

The Wikipedia entry is pretty unbiased and informative as well: http://en.wikipedia.org/wiki/Synthetic_oil


Of course, the reason why driving enthusiasts always get embroiled in the synthetic vs conventional battle is whether the advantages of synthetic oil (those that have been scientifically verified, and there are many) outweigh the disadvantages (mostly cost). The bottom line is that conventional oils work fine for average driving in moderate temps. I got used to using it in my Audi because my lifters pumped up quicker in cold weather (fact 15 seconds vs 2 seconds. I measured it with a watch. Don't assume anecdotal data are not factual; you can question reliability and how broadly the observation generalizes to other circumstances, but don't condemn anecdotal data out-of-hand. Instead analyze it for potential flaws or alternative interpretations, and whether you can trust the source). Also don't forget that was a turbocharged engine with the turbo bearings subjected to really high temps, and they were lubricated by engine oil (and cooled by a water-jacket also). I wanted an oil in there that would hold up to that heat and get lubricated quickly on those -20 F days. There were a lot of turbo bearings failing from lube issues (Audi even went to two oil filters in earlier versions). I wanted every lubrication advantage I could get so I paid for synthetic. Similar rationale often used by Harley owners when thinking about the back cylinder that was smoking hot while stuck in traffic.

And this post takes me to the end of my involvement in the synthetic/conventional debate. I've seen too many of these in other forums to know that these debates devolve rapidly.

iolmaster

iTrader: (1)

I do not trust Popular Mechanics just like I don't trust Stereo Review in my other hobby. It is a rare occasion that any of these magazines say anything negative about a potential advertising client. They pander to the advertisers. If there was less fuel being consumed, the government would be mandating a switch to synthetic. It has never been proven that the "superior" characteristics of synthetics have a real effect on engine wear in normal engines under normal operating conditions. There is no question that synthetics have enhanced capabilities in extreme conditions like jet engines and race car engines. I am in fact looking for a peer reviewed study showing engines in normal cars last longer or get better gas mileage with synthetic vs. conventional oil. To this point I have yet to see one. The only advantage that has been proven is the fact that you can go a longer interval with synthetic. Please provide an unbiased, peer reviewed study that shows this and I will eat my words and immediately switch to synthetic oil. I had a 1991 Mercury Sable that went 250,000 miles with 5,000 mile change intervals and it was running fine when I sold it. That is my anecdotal evidence. Not much use either, in my opinion. And no, I do not mistrust scientists. They are the ones I do trust. The article you provide is not presented by scientists.

Jabberwock

I think we are gonna have to agree that there are multiple viewpoints on this particular debate. Clearly it lacks a "smoking gun" proof of a high quality double blind serious journal study to prove it one way or the other.

So there will remain lots of smoke and hot exhaust gas in the air surrounding this debate - and some of it is coming from cars : )

kjcole

Which one? Surely you can't mean the review paper (1984) I cited. Those people seem to be scientists (but they also are engineers employed by Mobil, just to see if the conspiracy theorists out there will jump on it). In that peer-reviewed paper they do a pretty good job citing 50 years of independent research from academic scientists and industrial scientists (mostly chemical engineers) documenting how various synthetic formulations behave (the good and the bad) in bench testing.

Last comments, honestly. The reason you can't find a peer-reviewed, double-blind study, of real cars in real use is that the chemical engineers who developed and tested these lubricants since the 1930's have established conclusively the behaviors of these lubricants as a function of temperature, load, blah, blah. Just read summaries of Zorn's original work for a start, and then another 70 years of research. Look, you can conduct such a study but you won't get it published because the reviewers and editors will reject the manuscript with a terse review saying that the results were predictable based on the existing scientific knowledge. In short, they won't waste journal space. What will you write in the Introduction for your study rationale? --- "I don't trust the past 70 years documenting the development and testing of synthetic lubricants which firmly establish material properties and behavior in a variety of engines and operating conditions. So I did this double-blind study." Here's how such a study would get published .... if the results in fact didn't follow from the known properties of the lubricants AND the methods and data analyses held up to peer-review. And we haven't seen that study yet, have we? Trust me, I'm a scientist:>)



BUT, look at the Consumer Reports NYC taxi test, which supports both of us when we say that under normal conditions you don't need synthetic oil in our cars....

Sorry if I offended anybody, but you just can't say that there's no evidence that synthetic lubricants show superior performance at extremes of operating temps, reduced sludging, blah blah. There's 70 years of peer-reviewed research in scientific journals, but you have to go to the library - or pay the on-line access fees, and then jump into those chem engineering and related journals. Whether the performance benefits outweigh the cost for YOUR car and use, well that is very debatable. Yes, AMSOIL and ExxonMobil, etc are snookering some people who are paying for something that isn't as beneficial for their use as the ads would have them believe.

Signing off.