The Big Oil Post

[Cobra'03]

These are the most comprehensive and recent ones I could find. They date to March 2003 and May 2003. I will post the numbers, add a comment or two, and answer any questions you may care to pose. These tests were commisioned by Amsoil, but since they use standardized ASTM protocols, they could easily be verified, and any deception challenged. Based on my experiences with the products from all these companies, and the results of similar but less comprehensive tests posted elsewhere, these do not look doctored or suspect. But as I did not oversee them, I cannot and will not be accountable for any discrepancies, real or imagined. This was a lot of work to type, and I strived to get them right.

1. All the oils were 10w30 viscosity
2. The oils tested were:
Amsoil (syn)
Castrol GTX Drive Hard (mineral)
Valvoline Synpower (syn)
Mobil Drive Clean (min) - isn't this the rebadged Honda oil?
Pennzoil Purebase (min)
Quaker State (Syn)
Quaker State Peak Perf (min)
Castrol Syntec (syn)
Valvoline (min)
Pennzoil Synthetic (syn)
Mobil1 SuperSyn (syn)

The following ASTM tests were run:
Thin-film Oxygen Uptake ( D-4742)
High Temp/High Shear ( D-4683)
NOACK Volatility ( D-5900)
Pout Point (D-97)
Total Base Number (D-2896)
Cold Cranking Simulator D-5293)
4-Ball Wear (D-4172)
*********************************************************
Test 1: Thin Film Oxygen Uptake:
Measures the oxidation stability of an oil.
The induction time (break point) in minutes is measured. The test uses standard amounts of fuel dilution, soluble metals, and water to offer a real-world applicability.

Results for this test(all units in minutes):
Amsoil: >500 (no break)
Mobil1: 397
Pennzoil Purebase: 242
Castrol Syntec: 221
Valvoline: 219
Vavoline SynPower: 211
Mobil Drive Clean: 209
Quaker State Peak Performance: 192
Pennzoil Synthetic: 159
Quaker State Synthetic: 159
Castrol GTX Drive Hard: 132

Test 2: High Temperature/High Shear (HT/HS)
Measures a lube's performance under severe heat and shear (mechanical stress) as would be found in the journal bearings under heavy load. The units displayed are viscosity based, using the centipose unit (cP). The minimum spec for a 30w is 2.9 cP.

Results for this test (all units in cP):
Amsoil: 3.51
Quaker State Peak Performance: 3.37
Castrol GTX Drive Hard: 3.35
Vavoline SynPower: 3.30
Mobil1: 3.30
Valvoline: 3.30
Mobil Drive Clean: 3.28
Pennzoil Purebase: 3.16
Quaker State Synthetic: 3.15
Pennzoil Synthetic: 3.14
Castrol Syntec: 3.13

Test 3: NOACK Volatility.
Measures the evaporative loss of lubricants in high temperature conditions. The higher the number, the thicker the lubricant will become. API SL and GF-3 specs allow for a 15% evaporation limit. In this test, obviously, lower is better. Syns almost always have an advantage due to their monomolecularity.

Results for this test (% weight loss):
Amsoil: 4.86
Vavoline SynPower: 7.03
Castrol Syntec: 7.77
Quaker State Synthetic: 7.80
Pennzoil Synthetic: 8.15
Mobil1: 8.92
Castrol GTX Drive Hard: 8.93
Quaker State Peak Performance: 10.63
Mobil Drive Clean: 10.83
Pennzoil Purebase: 10.93
Valvoline: 12.18

Test 4: Pour Point
This test reveals the lowest temperature at which a lubricant will flow when cooled under test conditions. The lower, the better the product will perform in getting from the oil pan to the upper oil galleys, and in providing oil pressure quickly. Synoils generally are the best, because they are free of wax crystals, but today's mineral oils are better refined to remove wax impurities, and use advanced pour point depressant additives to help offset the synoils' intrinsically better properties.

Results for this test (all units in degrees Centigrade):
Amsoil: -48
Mobil1: -46
Vavoline SynPower: -46
Castrol Syntec: -43
Pennzoil Synthetic: -40
Quaker State Synthetic: -40
Pennzoil Purebase: -37
Valvoline: -37
Mobil Drive Clean: -37
Castrol GTX Drive Hard: -37
Quaker State Peak Performance: -34

Test 5: Total Base Number (TBN)
TBN displays the lubricant's reserve alkalinity, and is, of course, the opposite of TAN (total acid number). A high TBN will help resist the formation of acids from sulfur and other sources. It is also a good indicator of reserve resistance to oxidation. The higher the number, the superior ability to suspend contaminants and the greater the ability to provide long-drain intervals
Results for this test (all units in mg KOH/g):
Amsoil: 12.34
Vavoline SynPower: 11.38
Castrol Syntec: 10.39
Pennzoil Synthetic: 9.73
Mobil1: 8.57
Valvoline: 7.88
Quaker State Synthetic: 7.82
Castrol GTX Drive Hard: 7.74
Mobil Drive Clean: 7.71
Quaker State Peak Performance: 7.55
Pennzoil Purebase: 7.40

RR's comments: I was very impressed with all the oils, as the mineral oils have significantly improved, consistent with previous comments about how mineral oils are closing in, and that the GF-3 spec has resulted in very good performing products. Mobil1's showing is the best i have seen for that product, which usually was in the 5-6 range previously. It certainly also supports my previous comments that the 3K oil change "necessity" is out of place with current technology. Like an enema for a dead man, while it may not help to do a 3K change, it wouldn't hurt I guess.

Test 6: Cold Crank Sumulator
This one determines the apparent viscosity of the oils at low temperatures and high shear rates, simulating the dreaded cold start. It has direct applicability to engine cranking, the lower the number the better in terms of stress on the battery, starter, etc. A 10w is tested at -25degF and must show a vis <7000 cP to pass.

Results for this test (all units cP at -25degC):
Pennzoil Synthetic: 3538
Amsoil: 3590
Mobil1: 3967
Quaker State Synthetic: 4142
Vavoline SynPower: 4541
Quaker State Peak Performance: 4620
Castrol Syntec: 4783
Castrol GTX Drive Hard: 5804
Pennzoil Purebase: 5936
Mobil Drive Clean: 6448
Valvoline: 6458

RR Comments: If you live and drive your car in very cold climates, the advantage of the synoils is obvious. Keep in mind that the NOACK performance figures here as well, as this tests hows the performance of fresh oil - after a few thousand miles, the oils with higher volatility will likely have thickened, unless there has been high dilution from fuel, such as can occur if excessive startup idling warmups are employed.


Test 7: Four Ball Wear
This one is a good indicator of the wear protection of a lubricant, although in the real-world it is should be factored in with the TBN of the oil. Three metal balls are clamped together, and a rotating 4th one is pressed against them in sliding contact. A scar is produced, since at some point the film strength (resistance to being squeezed out) of the oil will be exceeded. The scar is then measured, and the smaller the average wear scar, the better. This test is affected by both the base stock of the oil, and its additive package.

Results for this test (all units in inches):
Amsoil: 0.40
Castrol Syntec: 0.45
Vavoline SynPower: 0.55
Quaker State Synthetic: 0.55
Mobil Drive Clean: 0.55
Pennzoil Synthetic: 0.60
Mobil1: 0.60
Valvoline: 0.60
Castrol GTX Drive Hard: 0.60
Quaker State Peak Performance: 0.60
Pennzoil Purebase: 0.65


RR Comments: Amsoil and Castrol Syntec are the clear frontrunners, indicating excellent chemistry and use of anti-wear additives. Once again, the high performance of the mineral oils against the 2nd tier synoils is notable, although one cannot dismiss the superiroity of the synoils across the board.

However, it is also admirable how well many of the mass-produced mineral oils fared. If you do frequent oil changes, they are very worth considering. The gap between synoil and the hydro-isomerized GIII mineral oils has significantly narrowed, especially when the GF-3 spec was implemented.

**************************************************************

Final comments:
I think that except for one of the lubes, there was a wide discrepancy of performance for the others - one might be good here, not so good there. As in life, consistency of performance is what sets apart the great from the good.
As Voltaire said, "The best is the enemy of the good". Perfectly good performance can be found in any of these products, and a thinking owner would factor his/her driving styles, operating conditions (environmental), maintenance schedule (intervals between changes), cost constraints, buy vs lease, and expected length of ownership into making a choice.

Now, what about the other top synoils? Well, they were not tested here, but certainly the industry giants were. Based on tests I have run or seen from sources I trust in the industry, Red Line, NEO, Motul, and others would likely score in the top quartile of these tests. The tests and UOA's I have seen for Royal Purple have never shown it to be other than mid-tier, competitive with the synoil or GIII mineral oils from the major companies.

Hope this is useful to you - I found it fascinating to watch the goo go head to head.

Happy Motoring!!

 

[lethal]

NICE write up. Your comments are great, I appreciate it man.

How is that Ford GT coming along =)

John

 

[JimBobWay]

Fantastic analysis! Thanks

 

[missile man]

Wonder Why Royal Purple, Red Line, or some of the other pure sythetics weren't included?

 

[oldmodman]

If I were Amsoil I'd sue! Imagine having no place to go but down!
I have always changed my oil every 3,000 miles and have been using Mobil 1 for about fifteen years. I wonder how Mobil 1 has evolved over that period of time?

 

[SnakeBit]

You have just validated my decision to go to Amsoil on the 03, although, I have had excellent results with Mobil 1 in the past, and would recommend it in a New York minute to anyone.

I have always used extended drain intervals with synthetic oil, and I'm always puzzled by people who change synthetics every 3,000 miles. Why not go with a good dino oil? The top brands have always tested well, especially when changed regularly. And they have a most favorable protection vs. $ rating under those conditions. I always have changed my oil filter every 3,000 miles (and top off, of course), but went a minimum of 6-9,000 miles between a full oil change with Mobile 1. I haven't quite decided yet on the Amsoil how long I'll go between a full change. I'll probably send in a sample for analysis at 6,000, then again at 9,000 before making the final decision, and just to keep it legit, I will be using Mobil's oil analysis instead of Amsoil's. I'll take the sample from the spill out after the old filter is removed (yeah, not the best place to get a sample, but unless I install a different pan plug, it'll have to do).

Cobra'03, any opinions on extended drain intervals?

 

[13 Cobra Toy]

Great post :bowdown: :bowdown:

Cobra'03,

How much better is the Amsoil S2000 than the reg Amsoil?

 

[chiliman]

COBRA03, since you're the oil expert.

So what should a person like me do. I've put less than 5000 miles on my Cobra in a year. Should I be changing at 3000 miles with dino oil, using synthetic and changing at 5000 miles or more, or just how often f it's a matter of that long before I put the mileage on the car?

Thanks

Randy

 

[Cobra'03]

Originally posted by 03 Cobra Toy
Great post :bowdown: :bowdown:

Cobra'03,

How much better is the Amsoil S2000 than the reg Amsoil?

That is a good question. Hard to answer, since S2k is an 0w30, and their "regular" is a 5 or 10w30. I ran the Series 2000 because of the possibility that their were tiny tolerances somewhere in the engine that would benefit from the 0w rating. I ran two analyses, and the series 2000 had higher TBN and larger amounts of the anti-wear additives. Is it really worth the extra coin. Only you can decide, that is a dollar thing. It is their best oil.

 

[Cobra'03]

Originally posted by chiliman
COBRA03, since you're the oil expert.

So what should a person like me do. I've put less than 5000 miles on my Cobra in a year. Should I be changing at 3000 miles with dino oil, using synthetic and changing at 5000 miles or more, or just how often f it's a matter of that long before I put the mileage on the car?

Thanks

Randy

You obviously either commute a short distance, or use your car for fun days in good weather. Is that about right? If I were you, I would run with Red Line, and change the filter every 6 months and add the makeup oil. Since I am guessing your car will sit for days without use, you want the protection that only an ester can give - it is polarized and attracted to metal, so it stays put.

Castrol makes an oil for Europe and Australia that of course they do not sell here - it is called Magnatec, and it is ester-based.
The following URL should help you all since it explains the benefits of ane ster-based synoil in layman's language:

http://www.castrol.com.au/products/magnatec/

If you really want to read some leading edge tribology, here is an article on nanolubrication, that shows that most oil dynamics occur at the 1st or 2nd molecular level. It may give you a headache if you like to watch MTV.

http://mechanik.tu-berlin.de/popov/publications/Nanowear.pdf

 

[chiliman]

Originally posted by Cobra'03
You obviously either commute a short distance, or use your car for fun days in good weather. Is that about right? If I were you, I would run with Red Line, and change the filter every 6 months and add the makeup oil. Since I am guessing your car will sit for days without use, you want the protection that only an ester can give - it is polarized and attracted to metal, so it stays put.

Yeah, it sits for long periods of time over the winter or in bad weather, etc. I'll only drive it when it's nice or in the mood.

What formula should I use? 5w30? I just had an oil change with Mobil 1 so should I change it right away? Although I'm not opposed to changing it right away why waste the cash if it isn't neccessary.

Thanks for your help

Randy

 

[TRBO VNM]

I am in a similar situation where I will only put 7 or 8k miles on my car. Only because I live 1.5 miles from work. It is daily driven, but my problem is in the winter now it won't get warm enough I don't think. I try to let it warm up for about 5 min or so and will try to sit and let it idle even after I come home just to let it warm up a bit more. Not sure if this is good or not.

I don't mind spending the extra money on a quality oil or even changing it every 3000 miles. I don't want to spend $50 per oil change, but 30 or 35 is fine with me. And I would rather change everything out and not just the filter.

I only have 2300 miles on the car now and was planning on switching at either 6 or 9k.

Can the amsoil be bought at local part stores? I haven't looked for it, so I am not sure. And what is the average cost per quart of their s2000?

thanks and I really appreciate all the info.

 

[SnakeBit]

As far as I know (which isn't very far), you can only get Amsoil from a dealer. I paid $103 for 12 qts. (ouch)

However, in the larger scheme of things, if I go 12,000 on a full change, that will be 6 1/2 qts plus 1 qt X3 (for the filter changes). So that's 10 qts in 12,000 miles. I'm also using Amsoil's $13 filters.

Still more expensive than Mobil 1, but then again I'm only putting 7,000 a year on the car, so overall, not too bad for a qood level of protection. Maybe not better protection than Mobil 1 would give me, I really don't know. I consider synthetic oil to be like insurance on a $13,000 engine.

Thing is, I might get the same protection by using Valvoline dino and Motorcraft filters and changing every 2,000 miles. But hey, it's MY MID-LIFE CRISIS and I'll spend the money for the peace of mind. Besides, it's cheaper than an affair (and subsequent divorce).

Giddy up.

 

[SnakeBit]

Originally posted by 03Redfiresnk
I am in a similar situation where I will only put 7 or 8k miles on my car. Only because I live 1.5 miles from work. It is daily driven, but my problem is in the winter now it won't get warm enough I don't think. I try to let it warm up for about 5 min or so and will try to sit and let it idle even after I come home just to let it warm up a bit more. Not sure if this is good or not.

I don't mind spending the extra money on a quality oil or even changing it every 3000 miles. I don't want to spend $50 per oil change, but 30 or 35 is fine with me. And I would rather change everything out and not just the filter.

I only have 2300 miles on the car now and was planning on switching at either 6 or 9k.

Can the amsoil be bought at local part stores? I haven't looked for it, so I am not sure. And what is the average cost per quart of their s2000?

thanks and I really appreciate all the info.

Since you have many short drives, I would suggest dino oil and frequent changes. The problem is that until the engine warms up, you might be getting gas in your oil. Less of a problem on the older Cobra engines b/c of the hypercrap pistons (sorry, I can't spell the correct name, but they have a higher silicon content and much less thermal expansion than forged parts do). This will reduce the lubricating properties of your oil. Maybe Cobra'03 will chime in and verify this (or maybe he'll raise the BS flag on me). Anyway, that's my opinion on your situation.

 

[TRBO VNM]

snakebit,

thanks for the help. hopefully cobra03 will chime in with his opinion. I am use to using either mobil 1, castrol gtx or their syntech. So I haven't even heard about the Dino oil. All I know is what I have seen mentioned on here. Is that a brand name or something? Is that bought a special places as well? And I assume it has the same weights like other oils to choose from.

On a side note, when I brought my car to the dealer today I asked the service rep about using synthetics and I understand he and SVT say to use this one or that one and why, but he did say as posted here, as long as they meet the SAE requirements and you save your receipts in case something does happen to your motor, using other oil products/weights will not void your warranty.

 

[BoneCrusher]

Cobra'03
Whew, my hands hurt from just thinking about all that typing you did. We are all, once again, indebted to you. That info helped us all out. Thanks.

 

[missile man]

Been using Royal Purple in my snake and all family cars for about 2 years now all on extended intervals. No problems at all and RP is cheaper than Amsoil.

 

[Cobra'03]

Originally posted by chiliman
Yeah, it sits for long periods of time over the winter or in bad weather, etc. I'll only drive it when it's nice or in the mood.

What formula should I use? 5w30? I just had an oil change with Mobil 1 so should I change it right away? Although I'm not opposed to changing it right away why waste the cash if it isn't neccessary.

Thanks for your help

Randy

Use 10w30 in summer, 5w30 in winter, 0w30 year round

To the guy who warms his car up for 5 minutes - this really is not a good idea - it is best to drive off - as long as you get the oil temp up once a week or so, the oil will not degrade, compared to the heavier dilution and corrosion that can occur from an idle war-up.

 

[Cobra'03]

Originally posted by lethal
NICE write up. Your comments are great, I appreciate it man.

How is that Ford GT coming along =)

John

Well, I called the GM the other day, and said when am I going to get my car. He of course hemmed and hawed, and finally said that they could not sell it at the MSRP, so of course I punted on it.

Really, I never figured I wouyld get it at MSRP, but would have bought it - I certainly would have asked to drive it before making my decision, and that drive would have scared the holy pizzle out of the salesman, I assure you. I would have had my pound of flesh - or rubber.

Oh well, I am building up my little jewel from Tochigi, one of the last to be made at the NSX plant. S2000 production is moving to a typical Honda mfg facility, so the panache of having a car hand-assenbled by the select crews who assemble the NSX is gone.

 

[SinisterX]

Cobra 03, good job

And that is why Im a Amsoil member, and buy it for cost