1) "better" is a highly subjective term and concept, for that matter. when discussing which is better, establish cirteria first, THEN provide evidence. Not vice versa.

2) synthetics have a wider temperature range than multigrade dino oil because they have been designed that way. one of the side effects of this is that the synthetic is a thinner oil. compare 5w15 dino to 20w50 dino and then compare them to 5w50 synth. you'll see that the viscosity of the synthetic is closer to that of the 5w15.

3) point #2 is possible becuase sythetic oils resist thermal breakdown to a greater degree than dino oils. why? because oil companies have taken all of the most desireable properties of all dino oils and combined them (as much as possible) into a single product.

4) synthetic oils do not, repeat NOT, cause leaks. their lower static viscosity (as explained in point #2) just makes EXISTING leaks more apparent.

5) a few people have mentioned that their vehicles seem to have more power and rev more freely after converting to synth. again, see point #2. oils with lower viscosity (aka thinner oils) require less effort to move and move through. this is why "winter grades" are thinner oils than "summer grades".

6) the purpose of crankcase oil is to a) lubricate wear surfaces, b) aid in cooling the wear surfaces, c) coat surfaces to prevent oxidation (and thus corrosion) and d) to act as a suspension for wear particles and other impurities in order to keep them away from wear and bearing surfaces and therefore reduce secondary wear.

[primary wear occurs when one component wears against another component creating the particles that are suspended in the oil. secondary wear is the wear that occurs when these particles come into contact with the bearing surface and causes more wear.]

7) ever hear of "breaking in" an engine? remember how you used to have to change the oil every 300-500 miles or so when you bought a new car? this was to remove those particles in point 5d because they pretty much act like a fluid borne abrasive and can cause a lot of damage. it was particularly critical to change oil frequently during the break-in period because manufacturing technology at the time was not as precise as it is now.

current technology allows manufacturing processes to make parts to much higher tolerances ensuring much better fit of assembled parts. ie. not as much wear occurs in the "break-in" period because the parts fit so well to start with.

8) the whole point of changing the crankcase oil is to remove the particles that are suspended in the oil. yes, the old oil has broken down and does not offer the protection as a fresh batch of oil, but let's assume that oil companies have engineered an oil that never suffers from thermal breakdown. you would STILL have to change your oil on a frequent and regular basis to remove the particles suspended within.]

9) i've no doubt that synth breaks down at a much slower rate than dino oil. this is a godsend for engines which see extreme conditions. the most common example is racing engines. there are all kinds of ads and commercials out there about how race car drive X and his team only use synthetic oil whatever.

9a) first of all, realize that the participation of race car drive X and his team is PAID FOR by oil maker whatever. if another oil company offered them more money, it's likely that they would switch brands.

9b) secondly, racing engines are rebuilt after each race with most races averaging 500 miles or less, you're not really going to see much in the way of wear.

if you want to be impressed, check out Mercedes' corporate site where they report the World Record Time-to-Distance runs of the C-111 and the early 190E 2.3-16. THREE 2.3-16s ran for over 201 hours nonstop (except for refuelling stops and driver changes which averaged 20 seconds, and "major" maintenance stops -oil changes and tire changes- which lasted only a few short minutes).

for those of you without calcualtors handy 201 hours translates to a little over EIGHT DAYS. keep in mind, this was eight days non-stop in 1983. only one car had a mechanical failure and that was a broken distributor shaft. upon examination of the engines after the run, the internals showed only minimal wear. oh...the distance travelled was 50,000 km.

10) getting back to the whole syth vs. dino debate, chemistry and technology has elevated to the point that there is little difference between oils and their performance these days. many MB owners figure that because there's a sticker on the car that sayds "Mercedes-Benz uses Mobil 1 Oil" that Mobil 1 is the best out there. again, read points 9 and 9a above. this is not to say that Mobil is an inferior oil, just don't believe everything you read or are told.

11) the idea of keeping any oil, synthetic or otherwise, in an engine for more than 5000 miles is ludicrous. synthetics may have an effective life of over 5000 miles but that doesn't mean that it will keep the metal shavings and filings away for 5000 miles.

think about it. your engine redlines at 7700 rpm, does that mean that when you drive you do/should rev that high all the time?

The bottom line here is that the technologies have gotten so good that there isn't much difference between brands and/or types of oils anymore. the most important thing to remember is that you HAVE to get the particles out of your engine. and the ONLY way to do that is to change your oil frequently and regularly. whether you use synth or dino oil is ultimately up to you.

personally, with synth being twice the cost, I'm quite content to continue using dino oil in all 5 cars and changing it out at 3000 miles.

__________________
'94 W124.036 249/040 leder; 8.25x17 EvoIIs
'93 W124.036 199/040 leder; 8.25x17 EvoIIs, up in flames...LITERALLY!
'93 W124.036 481/040 leder; euro delivery; 8.25x17 EvoIIs
'88 R107.048 441/409 leder; Euro lights
'87 W201.034 199/040 leder; Euro lights; EvoII brakes; 8x16 EvoIs - soon: 500E rear brakes
'70 R113.044 050/526; factory alloys; Euro lights

According to the oil company chemist I was working with (on a distillation project) about 7 years ago, synthetic oil have better lubricating properties -- squeeze out, abrasion resistance, detergent ability, and friction reduction. Often by an order of magnitude. They also "wet" metal surfaces much better than mineral oils, either paraffinic or linear hydrocarbon.

The result is that they are MUCH better lubricants, no matter what the application, than mineral base oils, and by chemical nature have far less viscosity variation with temperature. They, again by their chemical nature, resist oxidation at high temps much better, and do not "tar" when they start to degrade.

You can get the same serivce, more or less, other than varnish buildup, out of dino oils IF you change them (with filter change) every 3000 miles. Synthetics are limited by soot buildup in diesels, so old technology engines can be a problem due to soot accumulation (and blowby hydrocarbons accumulating -- this raises the viscosity considerably). As far as wear preventing characteristics, synthetics can go for extended periods without degredation so long as the filter is changed fairly often. Dino oils will sludge at the recommended intervals in heavy duty use, synthetics won't.

This is all documented, not urban legend. Commercial jet engines have ALWAYS been run on synthetics -- dino oils char and blow the engine up, as the military found out in the 50s. The resistance to using synthetics is due to their cost.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

"This is all documented, not urban legend"

Where is it documented and is the author an independent source?

Precisely.

__________________
'94 W124.036 249/040 leder; 8.25x17 EvoIIs
'93 W124.036 199/040 leder; 8.25x17 EvoIIs, up in flames...LITERALLY!
'93 W124.036 481/040 leder; euro delivery; 8.25x17 EvoIIs
'88 R107.048 441/409 leder; Euro lights
'87 W201.034 199/040 leder; Euro lights; EvoII brakes; 8x16 EvoIs - soon: 500E rear brakes
'70 R113.044 050/526; factory alloys; Euro lights

Don't bring in the arguement that jet engine/aircrafts only use synthetic to support their use in a regular road car. These are two totally different applications, totally different engines with totally different engine oil.
The race car arguement is not valid neither. The type of oil a race car uses (Nascar, CART, F1 and others) is only an indication of which sponsor pays the most. There again, they are totally different applications.
For those who say they have withnessed 10% decrease in fuel consumption or "felt" a smoother or stronger engine when using synthetic oils, I'd say this is bull****. I and my team have performed several hundreds of highly sophisticated laboratory controled tests on engine oils (mineral, synthetic and blends) fuel economy is not a factor, engine smoothness is not a factor.
Just imagine walking in a conference room with dozens of highly qualified GM or Ford engineers with a claim saying "My new miracle oil will give you 2% free fuel economy. The meeting will be over in 1 minute flat.
Again. synthetic oils are very good oils but, again, for normal street going production cars run in normal conditions, there is no financial/mecanical/longevity benefit to be derived.
JackD

Jackd,
Again, you hit the mark. If Synthetics actually provide a 10% increase in fuel economy then don't you think this story would be on the back on every bottle and possible lead to govmt regulations that mandate the use of synthetics. Imagine if our country could change to use 10% less fossil fuel. Even a 2% drop in usage would have an incredible effect on the ecomomy.

In any case, my car seems to run better and rev smoother when it's clean.... I'm serious. But I know that this is just my own perception that results from an external appearance.

It would be nice to line up ten cars, five dino, five synthetic, all the same mileage and same model. The experts that can feel the difference would then be able to drive all the cars and tell us.

Did you know that Mobil 1 ran a BMW in house tredmill test machine what ever for 1 Million miles. Then they tore the engine down and all the components were still with factory spec. It's was on there web site, not now? They do have FAQ on a 200K test between Dino and Syn. I have also seen AmsOil test comparison that showed 0W40 Mobil 1 actually produced more HP on a Dyno. Intresting. The Ow40 probally helped with that but then again you can't buy 0w40 dino.

What ever I promise not to post again. There are alot of X VS. X oil test out there. These oil threads always get intresting on any type of Auto board.

Agreed.

Once again, agreed. And thank-you supporting my statement to the same effect

Precisely my point.

__________________
'94 W124.036 249/040 leder; 8.25x17 EvoIIs
'93 W124.036 199/040 leder; 8.25x17 EvoIIs, up in flames...LITERALLY!
'93 W124.036 481/040 leder; euro delivery; 8.25x17 EvoIIs
'88 R107.048 441/409 leder; Euro lights
'87 W201.034 199/040 leder; Euro lights; EvoII brakes; 8x16 EvoIs - soon: 500E rear brakes
'70 R113.044 050/526; factory alloys; Euro lights

Just because your engine has not reached these high "terminal" temperatures does not mean your oil has not been exposed to these same high temperatures. They most certainly have and this is one advantage of synthetics, making them "better" than dino oils.


glenmore
1991 300CE
1990 LS400

Stubman: Yes, I know about the BMW test. I even have a copy of the lab report somewhere in my files. I also have similar lab reports from Volvo, GM and Ford. All (mayby not all, but most) engine manufacturers perform these tests on a regular basis. Some use them in their advertizing, others not.
These test have nothing to do with the day-to-day operation of a car. No stop and go, not cold start/shut-down, no dirt, sand, no temperature fluctuations, almost constant loads en the engine, controled humidity and temperature, blueprint engines. One million mile might appear like an unachievable mileage, but under these conditions, it is nothing out of the ordinary.
Amsoil: Why don't have their lubricant approved/tested by API (American Petroleum Association)?, the only certification required by all engine manufacturers.
JackD

If you dismiss the syn users argument that the extra cost is worth whatever benefits they receive or perceive, than how do justify spending what you do on your oil? By your comparison above, you spend $2.00/qt? There is plenty of 79 cent oil out there.

glenmore
1991300CE
1990 LS400

to end the thread....

i have worked with a class of spark-ignited recips that i wager few at this site even know exist.

the engines are continuous-duty, stationary, industrial application engines. 4-stroke and 2-stroke. naturally-aspirated, blower scavenged, and turbocharged.

they are fueled by natural gas.

typically, they drive compressors, generators, pumps.

they operate 24 hours per day, generally at load factors of 90%-100+%. with up-times of 98%

engines operate in a diverse set of conditions, from the deserts of north africa, to the tropics of nigeria, to the tundra of prudhoe bay. and everywhere in between. offshore and onshore.

fuel is much more variable than the standardized chemistry of gasoline. from well-head gas to processed, unodorized gas to odorized, processed gas.

these recips are operated to make money.

considering the arguments that get advanced for synthetics, one would think that these engines would be using only synthetic lubricants. but the fact of the matter is, virtually none of these engines are operated using synthetics. not that they wouldn't work, it is just that a cost-benefit analysis has never shown a payoff for the higher cost.

interestingly enough, the only thing that has extended lube oil change intervals for these engines are engine-driven centrifugal oil filtration devices.

i should like to add that a very large number of these engines are operated by those companies that refine, blend lubricating oils. they have done their studies using their synthetics on these engines that they own and operate. their engines are still running with dino.

i care to add that for a large number of these engines, crankcase sample analysis is performed on a monthly basis. in fact, mobil, as one of the speciality suppliers of the oils blended for these engines, offered/offers their customers these analysis services as a part of their program. i share this with you so that you will understand that in this area of tribology, the oil companies and engine operators have a pretty extensive database of oils and their operating characteristics.

concluding, the only vehicle that i own and operate with enough mileage to be a valid specimen for this thread is my 1986 560sel. i am its original owner. it has been run on the m-b dealer's lube of choice[kendal] for approx 200,000 miles. then on valvoline at my indy garage. lube oil change intervals have ranged from 3,000 -7,500 miles. at about 210,000 miles, we did a top end[valves, guides, cams & timing chain] on the engine. cylinder bores, piston rings were still beautiful and compression was as if new.

my conclusion, dino is the cost-effective lubricant. i care to add that this car, like all my benzes, is run. piston crowns of this engine at tear-down were clean and free of any deposits. cylinder heads were also clean and free of deposits. so were the valves.

dino rules.

Thank you very much Albert.

Good night.


IN THE NEWS TOMORROW: How to save money by pushing the 87 octane button with no adverse effects.

I'm not dismissing anyone's argument, I'm just saying that I see many people espousing the virtues of one over the other in a hap-hazard manner. Furthermore, I was trying to clear up some issues/misconceptions such as

"synthetic lubricants cause leaks" - as i stated in my novel, sythetics don't cause leaks, but rather makes existing leaks more apparent because synthetic oils are a fluid that, while it provides the benefits of a thicker mineral oil, is thinner by nature and can pass through leaks more easily.

"synthetics are used by race team and mobil is used by Mercedes' F1 team, therefore it should be the best thing out there" - as earlier stated by myself and Jackd, racing teams will use whatever brand of oil gives them the most money. let's face it, motorsports is a business and a lucrative one at that. If Pennzoil went to McLaren Mercedes and offered them twice the sponsorship that Exxon/Mobil is currently offering them do you REALLY think we wouldn't be seeing the yellow Pennzoil logo on the new McLaren F1 car?

If synth advocates/disciples want to continue using synth oil at 2x the cost of mineral oil, I'm not going to stop them. Nor am I going to sit idlly by while misconceptions and misinformation is being spread about. I am not a chemical engineer, nor do i work in the oil industry. I am simply someone who doesn't take spoonfed information lightly and I prefer to do my own research and come up with my own opinion. and my opinion is this:

Synthetics provide better protection over longer intervals , this i do not dispute. HOWEVER, the MAIN reason for changing oils is STILL the removal of foreign particles that are suspended within the oil.

Regardless of what oil you use (hell...use canola oil if that makes you happy, i really couldn't care less) you HAVE to get that crap out of your crankcase. Why would you wait until 500-10,000 miles to do it? Because a label on a bottle says that the oil can last that long?

Ultimately, it's your perogative. Which I stated in my previous post. but maybe you missed the part where i said: "Whether you use synth or dino oil is ultimately up to you."

Personally, I change my oil every 3000 miles RELIGIOUSLY in ALL OF MY CARS. So, I'm not going to pay $5.00 CDN per Litre for synthetic when the benefit of using synthetic oils doesn't kick in until 5000 miles. I never run my cars on that long of an interval so why would i need an oil that lasts that long?

THAT is my justification.

__________________
'94 W124.036 249/040 leder; 8.25x17 EvoIIs
'93 W124.036 199/040 leder; 8.25x17 EvoIIs, up in flames...LITERALLY!
'93 W124.036 481/040 leder; euro delivery; 8.25x17 EvoIIs
'88 R107.048 441/409 leder; Euro lights
'87 W201.034 199/040 leder; Euro lights; EvoII brakes; 8x16 EvoIs - soon: 500E rear brakes
'70 R113.044 050/526; factory alloys; Euro lights

Ladies and gentlemen, ELVIS has left the building.

__________________
Learn as though you will live forever.
-Ancient Hindu Proverb
(Are there any modern ones?)

1998 E320 Blk\Blk
1995 BMW 530i (bad engine) sold
1989 BMW 535i sold after 170,000 fun miles
1996 Lincoln Town Car (6 passenger land barge, still smooth and quiet at 130,000 miles, make me an offer!)