synthetic oils?

yoyo25

Senior member
May 21, 2000
452
0
0
What are the benifits of synthetic oil? I am tempted to switch from the regular stuff to synthetic since it is fairly cheap now like from $22/oil change -> $37. I hear you can go like 7-10k miles instead of the regular 3-4k? Any thoughts? Is mobil1 a good brand?
 
Aug 23, 2000
15,509
1
81
mobil1 is what I use.
If you have an older car with over 100K miles, definatly switch to synthetic, it protects better, and is less prone to creating sludge.
 

Vette73

Lifer
Jul 5, 2000
21,503
9
0
Originally posted by: yoyo25
What are the benifits of synthetic oil? I am tempted to switch from the regular stuff to synthetic since it is fairly cheap now like from $22/oil change -> $37. I hear you can go like 7-10k miles instead of the regular 3-4k? Any thoughts? Is mobil1 a good brand?

Mobil 1 is good. But do not go over 6K. One of the reasons you change your oil is to get water, unburnt fuel, etc.. out of it. Oil and the filter cannot do this. A lot of Reg. Oil is ok past 3K BUT there is so much other stuff it can't do its job so you have to drain it.

 

amdskip

Lifer
Jan 6, 2001
22,530
13
81
AMSOIL 10W-30 Synthetic Motor Oil
*(6 quarts needed for 25,000 miles) @ $5.70/qt. x 6 = $34.20

Mobil 1 is a stripped down synthetic IMHO.
 

boyRacer

Lifer
Oct 1, 2001
18,569
0
0
If you're a real car freak... you'd use synthetic AND change oil in 3 months anyway. :) Mobil 1 is good but like people said don't go over 6k...
 

shiner

Lifer
Jul 18, 2000
17,112
1
0
Someone sent me this a while ago when I was looking at switching to Mobil 1. Not sure of it's origin.

More than you ever wanted to know about OIL
Choosing the best motor oil is a topic that comes up frequently in discussions between motoheads, whether they are talking about motorcycles or cars. The following article is intended to help you make a choice based on more than the advertising hype.
Oil companies provide data on their oils most often referred to as "typical inspection data". This is an average of the actual physical and a few common chemical properties of their oils. This information is available to the public through their distributors or by writing or calling the company directly. I have compiled a list of the most popular, premium oils so that a ready comparison can be made. If your favorite oil is not on the list get the data from the distributor and use what I have as a data base.
This article is going to look at six of the most important properties of a motor oil readily available to the public: viscosity, viscosity index (VI), flash point, pour point, % sulfated ash, and % zinc.
Viscosity is a measure of the "flowability" of an oil. More specifically, it is the property of an oil to develop and maintain a certain amount of shearing stress dependent on flow, and then to offer continued resistance to flow. Thicker oils generally have a higher viscosity, and thinner oils a lower viscosity. This is the most important property for an engine. An oil with too low a viscosity can shear and loose film strength at high temperatures. An oil with too high a viscosity may not pump to the proper parts at low temperatures and the film may tear at high rpm.
The weights given on oils are arbitrary numbers assigned by the S.A.E. (Society of Automotive Engineers). These numbers correspond to "real" viscosity, as measured by several accepted techniques. These measurements are taken at specific temperatures. Oils that fall into a certain range are designated 5, 10, 20, 30, 40, 50 by the S.A.E. The W means the oil meets specifications for viscosity at 0 F and is therefore suitable for Winter use.
The following chart shows the relationship of "real" viscosity to their S.A.E. assigned numbers. The relationship of gear oils to engine oils is also shown.

_______________________________________________________________
| |
| SAE Gear Viscosity Number |
| ________________________________________________________ |
| |75W |80W |85W| 90 | 140 | |
| |____|_____|___|______________|________________________| |
| |
| SAE Crank Case Viscosity Number |
| ____________________________ |
| |10| 20 | 30 | 40 | 50 | |
| |__|_____|____|_____|______| |
______________________________________________________________
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
viscosity cSt @ 100 degrees C
Multi viscosity oils work like this: Polymers are added to a light base (5W, 10W, 20W), which prevent the oil from thinning as much as it warms up. At cold temperatures the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.
Multi viscosity oils are one of the great improvements in oils, but they should be chosen wisely. Always use a multi grade with the narrowest span of viscosity that is appropriate for the temperatures you are going to encounter. In the winter base your decision on the lowest temperature you will encounter, in the summer, the highest temperature you expect. The polymers can shear and burn forming deposits that can cause ring sticking and other problems. 10W-40 and 5W-30 require a lot of polymers (synthetics excluded) to achieve that range. This has caused problems in diesel engines, but fewer polymers are better for all engines. The wide viscosity range oils, in general, are more prone to viscosity and thermal breakdown due to the high polymer content. It is the oil that lubricates, not the additives. Oils that can do their job with the fewest additives are the best.
Very few manufactures recommend 10W-40 any more, and some threaten to void warranties if it is used. It was not included in this article for that reason. 20W-50 is the same 30 point spread, but because it starts with a heavier base it requires less viscosity index improvers (polymers) to do the job. AMSOIL can formulate their 10W-30 and 15W-40 with no viscosity index improvers but uses some in the 10W-40 and 5W-30. Mobil 1 uses no viscosity improvers in their 5W-30, and I assume the new 10W-30. Follow your manufacturer's recommendations as to which weights are appropriate for your vehicle.
Viscosity Index is an empirical number indicating the rate of change in viscosity of an oil within a given temperature range. Higher numbers indicate a low change, lower numbers indicate a relatively large change. The higher the number the better. This is one major property of an oil that keeps your bearings happy. These numbers can only be compared within a viscosity range. It is not an indication of how well the oil resists thermal breakdown.
Flash point is the temperature at which an oil gives off vapors that can be ignited with a flame held over the oil. The lower the flash point the greater tendency for the oil to suffer vaporization loss at high temperatures and to burn off on hot cylinder walls and pistons. The flash point can be an indicator of the quality of the base stock used. The higher the flash point the better. 400 F is the minimum to prevent possible high consumption. Flash point is in degrees F.
Pour point is 5 degrees F above the point at which a chilled oil shows no movement at the surface for 5 seconds when inclined. This measurement is especially important for oils used in the winter. A borderline pumping temperature is given by some manufacturers. This is the temperature at which the oil will pump and maintain adequate oil pressure. This was not given by a lot of the manufacturers, but seems to be about 20 degrees F above the pour point. The lower the pour point the better. Pour point is in degrees F.
% sulfated ash is how much solid material is left when the oil burns. A high ash content will tend to form more sludge and deposits in the engine. Low ash content also seems to promote long valve life. Look for oils with a low ash content.
% zinc is the amount of zinc used as an extreme pressure, anti- wear additive. The zinc is only used when there is actual metal to metal contact in the engine. Hopefully the oil will do its job and this will rarely occur, but if it does, the zinc compounds react with the metal to prevent scuffing and wear. A level of .11% is enough to protect an automobile engine for the extended oil drain interval, under normal use. Those of you with high revving, air cooled motorcycles or turbo charged cars or bikes might want to look at the oils with the higher zinc content. More doesn't give you better protection, it gives you longer protection if the rate of metal to metal contact is abnormally high. High zinc content can lead to deposit formation and plug fouling.
The Data:
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 <1.5 .12

20W-40
Castrol Multi-Grade 110 440 -15 .85 .12
Quaker State 121 415 -15 .9 ---

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 --- ---

5W-50
Castrol Syntec 180 437 -45 1.2 .10
Quaker State Synquest 173 457 -76 --- ---
Pennzoil Performax 176 --- -69 --- ---

5W-40
Havoline 170 450 -40 1.4 ---

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

10W-30
AMSOIL 142 480 -70 <.5 ---
Castrol GTX 140 415 -33 .85 .12
Chevron Supreme 150 401 -26 .96 .11
Exxon Superflo Hi Perf 135 392 -22 .70 .11
Exxon Superflo Supreme 133 400 -31 .85 .13
Havoline Formula 3 139 430 -30 1.0 ---
Kendall GT-1 139 390 -25 1.0 .16
Mobil 1 160 450 -65 --- ---
Pennzoil PLZ Turbo 140 410 -27 1.0 ---
Quaker State 156 410 -30 .9 ---
Red Line 139 475 -40 --- ---
Shell Fire and Ice 155 410 -35 .9 .12
Shell Super 2000 155 410 -35 1.0 .13
Shell Truck Guard 155 405 -35 1.0 .15
Spectro Golden M.G. 175 405 -40 --- ---
Unocal Super 153 428 -33 .92 .12
Valvoline All Climate 130 410 -26 1.0 .11
Valvoline Turbo 135 410 -26 .99 .13
Valvoline Race 130 410 -26 1.2 .20
Valvoline Synthetic 140 450 -40 <1.5 .12

5W-30
AMSOIL 168 480 -76 <.5 ---
Castrol GTX 156 400 -35 .80 .12
Chevron Supreme 202? 354 -46 .96 .11
Chevron Supreme Synt. 165 446 -72 1.1 .12
Exxon Superflow HP 148 392 -22 .70 .11
Havoline Formula 3 158 420 -40 1.0 ---
Mobil 1 165 445 -65 --- ---
Mystic JT8 161 390 -25 .95 .1
Quaker State 165 405 -35 .9 ---
Red Line 151 455 -49 --- ---
Shell Fire and Ice 167 405 -35 .9 .12
Unocal 151 414 -33 .81 .12
Valvoline All Climate 135 405 -40 1.0 .11
Valvoline Turbo 158 405 -40 .99 .13
Valvoline Synthetic 160 435 -40 <1.5 .12
All of the oils above meet current SG/CD ratings and all vehicle manufacture's warranty requirements in the proper viscosity. All are "good enough", but those with the better numbers are icing on the cake.
The synthetics offer the only truly significant differences, due to their superior high temperature oxidation resistance, high film strength, very low tendency to form deposits, stable viscosity base, and low temperature flow characteristics. Synthetics are superior lubricants compared to traditional petroleum oils. You will have to decide if their high cost is justified in your application.
The extended oil drain intervals given by the vehicle manufacturers (typically 7500 miles) and synthetic oil companies (up to 25,000 miles) are for what is called normal service. Normal service is defined as the engine at normal operating temperature, at highway speeds, and in a dust free environment. Stop and go, city driving, trips of less than 10 miles, or extreme heat or cold puts the oil change interval into the severe service category, which is 3000 miles for most vehicles. Synthetics can be run two to three times the mileage of petroleum oils with no problems. They do not react to combustion and combustion by-products to the extent that the dead dinosaur juice does. The longer drain intervals possible help take the bite out of the higher cost of the synthetics. If your car or bike is still under warranty you will have to stick to the recommended drain intervals. These are set for petroleum oils and the manufacturers make no official allowance for the use of synthetics.
Oil additives should not be used. The oil companies have gone to great lengths to develop an additive package that meets the vehicle's requirements. Some of these additives are synergistic, that is the effect of two additives together is greater than the effect of each acting separately. If you add anything to the oil you may upset this balance and prevent the oil from performing to specification.

Kinda looks like crap on here....PM me if you want and I'll email you the original document.
 

trmiv

Lifer
Oct 10, 1999
14,670
18
81
LOL, shinerburke, I was just going to post some facts from the exact same article. I found it on the Crower Cams website though while researching recommending oils for Crower racing SBC pistons and cranks.
 

yoyo25

Senior member
May 21, 2000
452
0
0
Originally posted by: BoYRaCeR
If you're a real car freak... you'd use synthetic AND change oil in 3 months anyway. :) Mobil 1 is good but like people said don't go over 6k...

Thanks, good read!
 

BillGates

Diamond Member
Nov 30, 2001
7,388
2
81
Originally posted by: amdskip
AMSOIL 10W-30 Synthetic Motor Oil
*(6 quarts needed for 25,000 miles) @ $5.70/qt. x 6 = $34.20

Mobil 1 is a stripped down synthetic IMHO.

I'm still not sure about the AMSOil - I put it in my TL1000R after using Mobil 1 previously and all the time on my last bike (YZF600).

I instantly noted a much clunkier shifter feel and more effort (still nothing, but noticeable) to shift gears.

Whether or not that has anything to do with the amount of protection that one of the oils provides over another, it's hard to say, but I must say that the Mobil 1 gave me MUCH smoother shifting, and was cheaper.

-- I'm not sure what I'll put in it for the next change....
 

Ns1

No Lifer
Jun 17, 2001
55,420
1,600
126
37 dollar + labor oil changes suck =*(



24 for box of mobil1
13 for mobil1 filter
~10 for labo


= poor me
 

StageLeft

No Lifer
Sep 29, 2000
70,150
5
0
Originally posted by: NeuroSynapsis
37 dollar + labor oil changes suck =*(



24 for box of mobil1
13 for mobil1 filter
~10 for labo


= poor me
That's right and that's why I started doing oil myself last change. You just need car ramps, an oil filter wrench, and a cheap socket kit. All tools about $30 tops and it's shockingly easy to do - look for a how to on the net!
 

FenrisUlf

Senior member
Nov 28, 2001
325
0
0
I've been running Castrol Syntec in my truck for about 8 years. I noticed the difference at the first oil change - quicker revving and I picked up about 2 mpg. Since then I've put on about 70-80K miles and have had no problems. I change the oil between 3 and 5K miles. I've had no trouble with synthetics and think they're a good thing. I personally like the Syntec brand, but maybe it's because they've been doing it the longest and I used them first.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Synthetic oils are superior to petroleum oils in every aspect. Every aspect.

I've not found an oil that has better specifications than AMSOil oils. It seems hard to find specs for other oils, but AMSOil happy plants them right on their page.

You people that change your oil after 3k, and even 6k miles are just silly. ;) There should absolutely not be water and unburnt fuel in your oil if your engine is mechanically sound.

AMSOil's extended drain interval is 25,000 miles.. fully guarenteed. The 3,000 mile oil change is a myth.

That said, if you're really concerned about your oil and your cars engine, I suggest that you start having your oil analyzed every oil change. It's the only way to tell how well the oil you're using is working in your engine, and how long you could have left the oil in there before it needed to be changed.

Billgates - Are you sure the oil you used was recomended for a motorcycle? I would do a little more research regarding which AMSOil oil you should use in your bike before giving up on them. :)
 

LAUST

Diamond Member
Sep 13, 2000
8,957
1
81
Castrol Syntec 5W-50

Supercharged, just over 50K miles, every 3K still.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: FenrisUlf
I've been running Castrol Syntec in my truck for about 8 years. I noticed the difference at the first oil change - quicker revving and I picked up about 2 mpg. Since then I've put on about 70-80K miles and have had no problems. I change the oil between 3 and 5K miles. I've had no trouble with synthetics and think they're a good thing. I personally like the Syntec brand, but maybe it's because they've been doing it the longest and I used them first.

Nonsense. Everybody knows AMSOil was the first company to explore synthetic lubricants. As they say, AMSOil was the first in synthetics. :)
 

trmiv

Lifer
Oct 10, 1999
14,670
18
81
AMSOIL is great stuff. I use Redline in my motorcyle and car personally, but AMSOIL is great too. I would love to use AMSOIL in my race car, but the stuff is too expensive for the frequent oil changes we do (we use Valvoline Racing 20W-50). At oil changes every two weeks or so, 10 quarts per change, AMSOIL is a bit pricey. But for my street car it's Redline or AMSOIL.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: trmiv
AMSOIL is great stuff. I use Redline in my motorcyle and car personally, but AMSOIL is great too. I would love to use AMSOIL in my race car, but the stuff is too expensive for the frequent oil changes we do (we use Valvoline Racing 20W-50). At oil changes every two weeks or so, 10 quarts per change, AMSOIL is a bit pricey. But for my street car it's Redline or AMSOIL.

Geez, no kidding.. Do you use oil analysis? Do you really need to change your oil that often? :confused:
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Mobil 1 is a stripped down synthetic IMHO.
Mobil 1 is the synthetic. Mobil 1 was the first synthetic, and Mobil remains the industry leader because of continued product development. AMSOIL is a very good product too, but a person would have to be completely insane to go more than 10,000 miles between oil changes, and I highly dislike AMSOIL's claims that longer intervals are acceptable. I don't know a single mechanic who goes more than 7,500 miles even if they use high-end synthetics and baby the car. I don't go past 3,000 miles on any oil change, and after 215,000 miles my car still doesn't smoke or lose any measurable amount of oil between changes.

Synthetic oil's not the only thing to consider though. You'll need to make sure that you use a good oil filter, I would recommend Purolator or Wix/Dana (also sold as the Napa brand). Do not, under any circumstances, use a Fram oil filter. Fram's quality since Allied Signal bought them out has seriously declined. I wouldn't put a Fram filter on a rental car.

ZV
 

trmiv

Lifer
Oct 10, 1999
14,670
18
81
Originally posted by: Eli
Originally posted by: trmiv
AMSOIL is great stuff. I use Redline in my motorcyle and car personally, but AMSOIL is great too. I would love to use AMSOIL in my race car, but the stuff is too expensive for the frequent oil changes we do (we use Valvoline Racing 20W-50). At oil changes every two weeks or so, 10 quarts per change, AMSOIL is a bit pricey. But for my street car it's Redline or AMSOIL.

Geez, no kidding.. Do you use oil analysis? Do you really need to change your oil that often? :confused:

We just look at the oil and inspect the filter (cut apart) during oil changes.

It's a 500+ hp, 12.5 to 1 compression, 355ci small block chevy that sees 7000 RPMs, so we change the oil a lot. Better safe than sorry. Next year we will have a brand new 377ci 14 to 1 sbc that will make about 660hp, and regularly turn 75000-7800 rpms. That thing is getting really frequent oil changes.
 

PG

Diamond Member
Oct 25, 1999
3,426
44
91
I used Amsoil a while back in a car that I don't have anymore. I did the engine flush first and then followed all their recommendations. I used their oil filters and changed them as needed. The stuff really impressed me. Even after 25,000 miles when I had to change out the oil it still felt very slick between my fingers. It was sort of dark, but it sure was slippery. I've been meaning to start using it in my new vehicle but just haven't got around to it yet.
I don't see the point to using other synthetics. I could be wrong, but only Amsoil seems to really push the extended drain intervals which is not only good for the environment, but it saves work and time.




 

Vette73

Lifer
Jul 5, 2000
21,503
9
0
Originally posted by: LAUST
Castrol Syntec 5W-50

Supercharged, just over 50K miles, every 3K still.


You do know that Castrol Syntec is not a 100% synthetic oil right??

Mobil sued them for saying they were 100% synthetic oil. But they lost as the requirment to call your oil a synthetic is just to have most of the Additive package be syn. So only 10-20% of castrol syntec is true Syn.

But Mobil 1 is 100% syn.

I am not sure about the others. Does anybody else know about the other Syn's if they are 100% syn. like mobil 1 or like Castrol??

 

Vette73

Lifer
Jul 5, 2000
21,503
9
0
Originally posted by: Zenmervolt
Mobil 1 is a stripped down synthetic IMHO.
Mobil 1 is the synthetic. Mobil 1 was the first synthetic, and Mobil remains the industry leader because of continued product development. AMSOIL is a very good product too, but a person would have to be completely insane to go more than 10,000 miles between oil changes, and I highly dislike AMSOIL's claims that longer intervals are acceptable. I don't know a single mechanic who goes more than 7,500 miles even if they use high-end synthetics and baby the car. I don't go past 3,000 miles on any oil change, and after 215,000 miles my car still doesn't smoke or lose any measurable amount of oil between changes.

Synthetic oil's not the only thing to consider though. You'll need to make sure that you use a good oil filter, I would recommend Purolator or Wix/Dana (also sold as the Napa brand). Do not, under any circumstances, use a Fram oil filter. Fram's quality since Allied Signal bought them out has seriously declined. I wouldn't put a Fram filter on a rental car.

ZV

I was also about to ask how is Mobil1 stripped down. It is 100% syn.

But yes Zenmervolt is correct about Fram, they use paper for a bottom gasket now. Champion makes some good filters also, you can get them at Autozone under the name of STP.

 

alkemyst

No Lifer
Feb 13, 2001
83,769
19
81
keep in mind adding a synthetic to a high mileage engine may clean out deposits or flow through them that are now keeping your engine leak free.

Many also notice a large increase in oil usage on a higher mileage vehicle + synthetic.

These are not a fault for the synthetic, but problems nonetheless.