Synthetic Oils

[Eric Kasir]

Got this from one of the BBS's I'm on. Make quite interesting reading (if a little long..)

 

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Hi.Here is some oil info for anyone intersted.Mobil 1 is fully compatible with the elastomeric seals and gasket materials used in most modern engines.In engines that are in good condition,seal compatibility will not be a problem.Some older engines produced before the mid-1970s were manufactured with looser tolerances than today's engines.Low-viscosity grades of oil can leak from these engines.The solution is to use a higher-viscosity grade like Mobil 1 15W-50 to reduce this leakage which is what we use in most Ferrari's anyways.Contrary to what many may believe,synthetic lubricants are not a recent development.As early as the 1930s,Standard Oil of Indiana conductedresearch into synthetic oil.More serious development and production was commenced by the Germans during WWII, as their conventional lubricants congealed and froze on the Eastern front and stalled their advances into the Soviet Union.As jet engines were developed after the war,it soon became evident that conventional lubricating oils couldn't

withstand the high temperatures and pressures, and synthetics came to be used in all military commercial jet aircraft engines.Then in the 1960s history repeated itself, and it was again cold weather that spurred further development work as the U.S.Army needed better lubricants for Arctic and Antarctic use.Still later, NASA specified synthetic-based lubes for all space vehicles, including the Space Shuttle.Today's automotive synthetic lubricants have evolved as an almost direct result of these demanding military and extraterrestrial lubrication requirements.

The U.S. Department of Energy lists no fewer than *sixteen* performance

parameters for any modern automotive motor oil. These are:

 

-Low temperature fluidity (low pour point)

 

-Low volatility...i.e. resistance to evaporation and resultant oil

thickening...good oil economy, additional engine protection

 

-High temperature oxidation resistance (of the oil itself)

 

-Lubricity...the oil's slipperiness

 

-Thermal stability...resistance to performance loss due to temperature

change

 

-Compatibility with engine metals, elastomers (i.e. "rubber" seals), oil

filter elements, paints, and finishes

 

-Wear protection and film strength

 

-Freedom from deposit formation...good dispersant and detergent

characteristics

 

-Compatibility with other engine oils and additive packages

 

-Extended drain capability

 

-Water stability...propensity to remain separate of water molecules

 

-Corollary effects on an engine's octane requirements

 

-Ambient-startup protection...ability to protect against oil starvation

during initial startup

 

-Anti-rust properties

 

-Compatibility with catalytic emission control systems

 

-Compatibility with alcohol-containing fuels Low-temperature fluidity ("flowability") becomes an important consideration where winters are severe.Because synthetics are constructed "building block by building block",contaminates present in

petroleum oil which contribute to low-temp thickening are entirely

absent in synthetics, and fluidity is stable to as low as -65F.

Petroleum oils have an inherent percentage of paraffin crystals from

their crude oil origins.As temperatures drop, these crystals enlarge

and cause the oil to congeal.In extremely cold weather, petroleum oils

become a solid mass, thus impeding cold starts, and when the engine does

fire up, causing a period of engine operation without adequate

lubrication until the lubricant is warmed enough to allow proper oil

flow. Furthermore, because of synthetics' better ring-sealing

characteristics, fewer contaminants generated by fuel combustion are

allowed to escape into the oil pan. Thus the low-temp fluidity and

film-strength properties of synthetics both contribute significantly to

enginelife in colder climeates.In one

cold cranking test conducted by Mobil,at -30F, with Mobil 1 in the

crankcase, the engine turned at an average speed of 152 RPM, and

started; using 10W-30 and 10W-40 premium petroleum oils, the same engine

cranked at 45 and 32 RPM respectively... and failed to start. Mobil

states that its Mobil 1 (5W-30) all-season synthetic may be used *in any

engine* where 5W-30, 10W-30, 10W-40, or single-viscosity oil is normally

recommended by the manufacturer; its new "Formula 15W-50" synthetic is

designed to replace and outperform those SAE 15W-40 and 20W-50

conventional oils preferred by some drivers for use in high-performance

powerplants.

 

Ambient-start oil starvation is,at ANY TEMPERATURE,a major cause of

engine wear.Expert estimates vary as to how much abrasive wear is

attributable to lubrication-starvation during initial startups, but it

is generally conceded that a disproportionate share of an engine's

abrasion and wear is caused during those few moments after initial

cranking during which the oil has not yet reached full circulation. NEO

Oil Company, a well established and highly-respected producer of

synthetic lubricants, has recently developed an extended-life lubricity

additive for its synthetic motor oils specifically designed to remain on

the bearing surfaces after the engine shutdown and thus deliver

additional lubrication and wear-protection for initial startups.

 

On the other end of the thermal spectrum, synthetic oils are also

renowned for their high-temperature thermal stability. Superior

high-temp stability ensures and engine lubricant's capacity to protect

vital engine components during very-high-temperature operation, such as

hot summer driving, sustained high-speed driving, repetitious stop and

go metropolitan driving, driving in mountainous terrain,etc.Underhood temperatures also take a quantum leap with the use of Turbos,Superchargers or

power options,such as air conditioning b& because of emissions

devices and emissions-related engine redesign. It is important to note

that, even though the dash gauge may register only a 200F or so

water/coolant temperature, the temperature of the sump and of all the

assorted bearing surfaces significantly exceed the water temperature,

and OFTEN SURPASS 500F on the piston ring and cylinder wall areas.

These high-temperature surfaces serve to rapidly decompose petroleum oil

and additives, as well as contribute to their shorter service life,

while the synthetic is largely unaffected. Beyond the protection

afforded an engine during these particular instances of high-operating

temperatures, high-temp thermal stability moreover permits an engine

oil to deliver overall extended service life (significantly longer drain

intervals) in all driving conditions, because it prevents the phenomenon

of sludge and carbon deposit formations on critical engine parts

(valves, valve guides, oil channels,cam followers, piston rings,etc.

al.) due to oil thickening, a problem commonly attributable to petroleum

oil breakdown at high temperature. As these deposits accumulate in the

oil circulatory system, oil flow drops, thus accelerating engine wear.

To the user of synthetics, the benefits are (1) reduced wear of critical

engine components; (2) significantly reduced sludge and varnish... a

cleaner engine; (3) reduced engine drag due to uniform viscosity; and

(4) increased fuel economy due to reduced component wear.

 

Mobil Oil reported the results of simulated hot weather

performance with its Mobil 1 synthetic as evaluated by a standardized,

grueling engine test known as the Olds III-D. In this test, an

Oldsmobile 350" V8 engine is run for 64 hours at a 100-hp load and 300F

crankcase oil temperature. This test is designed to measure an oils

ability to resist oxidation and evaporation (and consequent thickening)

at high temperature. (If it seems odd that oil would *thicken* at high

temperature, consider the analogy of heating a pan of cold syrup on a

stove.At first it would become quite thinner, but if left for, say,

several hours, the resultant evaporation would cause the syrup to become

progressively thicker.) In order to qualify for the American Petroleum

Institutes top "SF" rating, a motor oil must pass the III-D test. This

means that it can thicken to no more than 375% of original viscosity at

the end of 64 hours of continuous running. Mobil states: "To test the

extra stability provided by the Mobil synthetic oil, we decided to run

the III-D *for 128 hours*...double its normal length...and without oil

drain. The Mobil 1 synthetic easily passed the test under these brutal

conditions, thickening only an insignificant 20%. For comparison, a

high-performance premium conventional oil was tested under identical

conditions. That test had to stop at 96 hours; the oil had turned

solid. Another premium conventional oil forced the the test to stop at

112 hours, well before the end of the scheduled double length." Amoco

Conducted an identical double-sequence III-D test on its Ultimate 5W-30

synthetic; it also passed the test with flying colors, thickening only

18%.

 

"Film strength" refers to the amount of pressure required to force out a

film of oil from between two pieces of flat metal.The higher the film

strength,the more protection is provided to such parts as piston rings,

timing chain, cams, lifters, and rocker arms...wherever the lubricant is

not under oil-system pressure.Synthetics routinely exhibit a nominal

film strength of well over 3,000 psi, while petroleum oils average

somewhat less than 500 psi.The result is more lubricant protection

between moving parts with synthetics.The remarkable ability of synthetic oils to reduce internal operating

temperatures is far too important to ignore, since high operating

temperatures contribute directly to premature failure of mechanical

components and gaskets and seals.Coolant (i.e. water/antifreeze) cools

only the upper regions of an engine.The task of COOLING the crankshaft,

main and connecting rod bearings,the timing gears and,the

camshafts and its journals,and numerous other components must borne

entirely by the oil.There are three identifiable reasons why synthetics do a better job of cooling an engine: (1) Because of both the

oil's lubricity (slipperiness) and it's stable viscosity, less

friction-- and thus less heat-- is generated in the first place; (2) The

molecular structure of the oil itself is designed to more efficiently

transfer heat, even compared against the thermal conductivity properties

(ability to absorb and dissipate heat) of an identical-viscosity

petroleum oil; and (3) As mentioned in the preceding paragraph, the more

rapid oil flow of these lower-viscosity synthetics contributes

significantly to the efficient transfer and dissipation of heat.

*Because of all these factors, oil-temperature decreases of from 20F to

50F are quite common with the use of synthetic oil*. One might even say

that the heat-reduction properties of synthetics are synergistic...by

helping to reduce its own temperature, the synthetic oil is

simultaneously enhancing the lubricant's overall performance

characteristics.

 

In a Popular Science article on synthetic oils, veteran race car

driver Smokey Yunick was quoted: "When you disassemble an engine that's

been run on petroleum oil, if you examine the rings and cylinder bores

with a glass you'll see ridges and scratches--that's the wear going on.

With polyol (a variety of synthetic), when you take the engine apart

everything has the appearance of being chrome-plated. In the engine we

ran at Indianapolis this year we used a polyol synthetic.When we tore

the engine down, you could still see the original honing marks on the

bearings...no wear at all.We put the same bearings back in because the

crankshaft never touched the bearings.

 

OIL performance RESULTS IN TESTS. compliled from various sources.Listed alphabetically --- indicates the data was not available

 

Brand VI Flash Pour %ash %zinc

 

20W-50

AMSOIL 136 482 -38 <.5>

Castrol GTX 122 440 -15 .85 .12

Exxon High Performance 119 419 -13 .70 .11

Havoline Formula 3 125 465 -30 1.0 ---

Kendall GT-1 129 390 -25 1.0 .16

Pennzoil GT Perf. 120 460 -10 .9 ---

Quaker State Dlx. 155 430 -25 .9 ---

Red Line 150 503 -49 --- ---

Shell Truck Guard 130 450 -15 1.0 .15

Spectro Golden 4 174 440 -35 --- .15

Spectro Golden M.G. 174 440 -35 --- .13

Unocal 121 432 -11 .74 .12

Valvoline All Climate 125 430 -10 1.0 .11

Valvoline Turbo 140 440 -10 .99 .13

Valvoline Race 140 425 -10 1.2 .20

Valvoline Synthetic 146 465 -40

15W-50

Chevron 204 415 -18 .96 .11

Mobil 1 170 470 -55 --- ---

Mystic JT8 144 420 -20 1.7 .15

Red Line 152 503 -49 --- ---

15W-40

AMSOIL 135 460 -38 <.5>

Castrol 134 415 -15 1.3 .14

Chevron Delo 400 136 421 -27 1.0 ---

Exxon XD3 --- 417 -11 .9 .14

Exxon XD3 Extra 135 399 -11 .95 .13

Kendall GT-1 135 410 -25 1.0 .16

Mystic JT8 142 440 -20 1.7 .15

Red Line 149 495 -40 --- ---

Shell Rotella w/XLA 146 410 -25 1.0 .13

Valvoline All Fleet 140 --- -10 1.0 .15

Valvoline Turbo 140 420 -10 .99 .13

The numbers above are not, by any means, all there is to

determining what makes a top quality oil. The exact base

stock used, the type, quality, and quantity of additives

used are very important.The given data combined with the

manufacturer's claims,your personal experience, and the

reputation of the oil among others who use it should help

you make an informed choice.Hope this helps some of you.Regards.Nick Scianna. www.nicksforzaferrari.com