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Most of their oils will not officially meet API/ACEA and the accompaning OEM standards because they have chosen not to have their oils tested. So you really have no idea how well the oil will perform for your application. (UOA does not tell you that). That being said they have been around a long time and if their oils were not up to standards I would no think they'd be around today. Personally if you're under warranty stick with oils which have OEM approvals.
Has any global automotive company high performance or otherwise ever did a deal with Amsoil as selected OEM oil of choice?
Amsoil, as well as Redline, Royal Purple, and others are "boutique" oil products companies with small technical, engineering and chemistry staffs. They survive utilizing strong marketing influence in the aftermarket world. They're nowhere near the size of the technical staffs of the industry giants and it would be far fetched and risky if a world class car manufacturer endorsed them, and typically, they won't even evaluate their offerings as alternatives because of the risk.
The biggest most visible customers for these boutique companies are in the race world. They pay for a car to get their name on the car and an endorsement from the driver. Whether they even use the product in their race car or not no one knows, but they'll take the money to say they did.
Last edited by Alea_Iacta_Est; Oct 23, 2020 at 07:09 AM.
When I do get my C8...eventually, I'll stick with the factory swill.
I've run Motul in everything I have owned with an engine since 2000 and just prefer the consistency and the oil lab results over time. As I really have no data beyond what i personally used to compare it to in each case, I just stuck with it. Motul is expensive, but their 0W level oils hold up really well and survived 6000 miles in my '09 CBR1000RR that was putting down about 230whp at the time (all motor). I used it in a ton of sport bikes, my '98 Supra, '02 3000GT VR4, '13 FRS, '15 C7, and '15 Mustang GT with no issues other than getting oil lab results that said that my oil was basically still effectively new at my regular oil change intervals.
With the Z06, I am going to play it safe because I figure that my first $100k+ car should adhere to specifications as long as it is under warranty to avoid any unnecessary costs. After that, who knows, I'll send my samples in to the labs and see how Mobil 1 holds up and may just stick with it...
I put 168,000 miles on a C4 using Mobil 1.
Put 128,000 on a C6 also using Mobil 1.
And put 97,000 on a '15 C7 before trading it for a '19 that already has about 8,000 miles on it...
No way I'm putting anything in there that is not factory recommended. This is a performance car designed FOR the oil specified.
Clearances, break in, extreme loads, all designed for the specified oil. If it was a race car where the motor gets rebuilt every so often or a 1970's muscle car sure.
For a performance car built in 2020, I'm not playing roulette with engineered specifications.
Probably just the Kool-aid I drank from Amsoil.
I use it in my Harley and Dodge Ram.
At least you understand you have "bought their Kool-aid!" Keep drinking for your bike and truck BUT use what GM recommends and has tested while your under warranty! After that if another "made from Natural Gas" or some other catchy phase has not caused you to switch on all your cars!
It discusses "synthetic oil" when it really was some ~20 years ago before Mobil lost a suit to Castrol who was calling a more highly refined "dino oil" synthetic. Forced Mobil and others to change their production to half the cost refined crude oil! From 1) What I read not sure Amsol is truly like the old Class IV "true synthetics" of old and 2) a petroleum engineer who visits the forum occasionally said for most applications the current oils do all that is needed and the old Mobil 1 may not have been as good!
My History with Mobil 1 goes back to 1974 when the Datsun district service manager recommended I find it and use it NOT in my engine but in the two large Hitachi SU carb dashpots! It solved what he called "porpoising!" It was the first year of manufactures using air pumps, very lean mixtures and in the case of the 260Z adding hot water passages in the intake manifold. Mobil 1 was being used by the military in Alaska etc and was hard to get. But I did and it solved the problem! Car no longer acted like a porpoise when accelerating when warm. Mobil 1 stayed at the same viscosity when warm and did not get thinner causing the large pistons in those SU's to bounce up and down! (By the way I ultimately blocked the water going to the intake manifold, added headers, removed the exhaust air pump and switched the Hitachi SU air/fuel mixture needle valves to ones having a richer mixture. The 260Z ran much stronger!)
Reading about it's high temp characteristics I realized the problem I had with my modified Corvair might be solved with this "true synthetic" Mobil 1. Even adding aluminum oil pan with external AND internal pin fins, aluminum valve covers to try and reduce oil temp, when driving aggressively the oil got to ~325F. An oil scum would form in the oil intake tube, it was obviously breaking down Even with the multiviscosity 40 weight I used. Mobil 1 solved that issue. It was hard to get and I had to buy by the case! Frankly since then have not had a car with high oil temps (frankly would add an oil cooler if I did as the corvettes' water oil heat exchangers in y C7s and now C8.
Group IV oils are still available in Europe but as I recall AMSOL just says they "perform like Group IV," not that they are or contain a majority of Group IV base oil.
People use them because amsoil is good at their marketing. Plus i'm sure the people who have to constantly spread positive feedback about it are usually secretly paid advertisers.
Use what is proven. Use what is recommended. Use what you have immediate access to.
That's mobil 1. I think they changed their specifications to meet GF-6 so if you get mobil 1 now, chances are it's the reformulated version. That's what i did just a month ago for my C7Z. I was using motul which is actually a very good oil, and dexos approved, but went back to mobil 1 because i don't like the price fluctuations with motul, and their inconsistent availability.
^^^^
Suggest you read the Car & Diver Link I posted in the post above yours. It's about 20 years ago when Mobil 1 lost a lawsuit to Castrol and changed the way Mobil 1 was made. They had to as what you get now is "dino oil" versus the Group IV what I call "true synthetic," but twice as expensive to produce!
Don't know how much Group IV base stock is in Amsoil BUT would not say it's trash. I never used it but IF significant amount of Group IV oil base stock is used it could have some benefits, AFTER THE WARRANTY is up!.
I have a neighbor who uses Amsoil. Says he changes the oil every 25K miles but he could go longer if he wanted since he drives mostly highway miles. When he changes it, he drains the oil, then starts his engine and runs it for about 15 seconds to completely purge oil from the pump and passages. He says, "I could drive it down the road and back if I wanted, because the Amsoil binds to the metal to make a superslick coating." Then he fills 'er up with his snake oil and he's good for another 25K miles.
In other words, you should use Dexos 2 rated synthetic oil like GM tells you to use. Save your receipts in case you need warranty work, because so far the LT2 has proven to have 1980s GM reliability.
^^^^
Hmm, I'd say your neighbor is wrong! No oil should be left in that long! Also changing once a year has always been suggested as the limit, as it's the crap that gets in from blowby etc that requires changing oil NOT that it is warn out!
Running the engine with no oil pressure is also foolish for the small amount of oil he's getting out of the pump!
^^^^
Suggest you read the Car & Diver Link I posted in the post above yours. It's about 20 years ago when Mobil 1 lost a lawsuit to Castrol and changed the way Mobil 1 was made. They had to as what you get now is "dino oil" versus the Group IV what I call "true synthetic," but twice as expensive to produce!
Don't know how much Group IV base stock is in Amsoil BUT would not say it's trash. I never used it but IF significant amount of Group IV oil base stock is used it could have some benefits, AFTER THE WARRANTY is up!.
If you're the type of person who changes their oil often, then going with amsoil is literally throwing money away.
Not to mention it's not dexos approved but that's besides the point.
I mean would you really want an oil that is advertised to "last" 25,000 miles? Even if that is remotely true, what about your oil filter? Would that last 25,000 miles?
I don't want to start an oil debate really, there's BITOG for that as there's a lot of phonies on that site. 90% of them really know nothing and just parrot what veteran members say, that's why i don't even browse that forum anymore.
But if mobil 1 did some trickery 20 years ago, i think of it like this. That was 20 years ago.
If GM puts mobil 1 from the factory, who am i to say that's not good enough? I don't know better. And i sure as hell won't trust any joe schmo off the interwebbzzzz to tell me which is better.
I like the mobil 1 price, and it's so easy to get, takes me 10 minutes to get from walmart and it's done. I don't need to wait for a package for amsoil to come. I don't need a membership, i don't have to listen to phony amsoil salesmen on the phone pitching me their service saying they'll deliver to my house for free. Buy a case get 6 quarts free or any of that bullshit.
Mobil 1 has been proven. And whatever was slacking back in the day i'm sure is fixed now.
Hell i don't even like castrol but i use magnatec in my new truck because my neighbor gave me 4 5qt jugs for free since he bought a tesla lol (that's one of the guys who i use as my feedback of how that car is, he hates it LOL)
Your neighbor is a fool who does not understand even the most basic fundamentals of how oil lubrication works in machines.
Inexcusable when a 2min google search will explain it all nowadays. Running an engine without oil is not too bright let alone driving the car in that state and putting a load on it.
Originally Posted by Zaro Tundov
I have a neighbor who uses Amsoil. Says he changes the oil every 25K miles but he could go longer if he wanted since he drives mostly highway miles. When he changes it, he drains the oil, then starts his engine and runs it for about 15 seconds to completely purge oil from the pump and passages. He says, "I could drive it down the road and back if I wanted, because the Amsoil binds to the metal to make a superslick coating." Then he fills 'er up with his snake oil and he's good for another 25K miles.
In other words, you should use Dexos 2 rated synthetic oil like GM tells you to use. Save your receipts in case you need warranty work, because so far the LT2 has proven to have 1980s GM reliability.
The C8 is an expensive car. Engine lubrication is crucial to engine longevity and problem-free operation. GM has set lubrication standards for C8 Corvette engines. Mobil1 0W40 meets or exceeds those standards and is the factory fill. I realize GM has contracted with Mobil1 at a favorable price to be the factory fill, but they could have done that with any engine oil manufacturer, so I don’t consider that to be a factor. To use an engine oil other than what is recommended by the manufacturer, which may or may not do its job as well, doesn’t make sense to me. And if it’s done to save money, that’s even less logical. Why would someone risk excess engine wear or even engine failure to save a few bucks a year? I think if GM engineers thought there was a better engine oil, that’s what GM would have contracted to use as the factory fill and would recommend to owners. Conspiracy theories aside, Mobil1 0W40 is the best engine oil for your C8, according to those who designed and built it, so why look elsewhere?
Why does every internet forum oil expert always think they know more than the people who designed & built the engine?
Oil is oil for the most part, and true synthetics are without a doubt the best thing to happen to lubrication since...well...ever. The Dexos 2 nonsense is just another hoop that oil manufacturers have to jump through and certification they pay for to get the shiny new label. Mobil 1 and GM have a business arrangement and they put this Dexos 2 label on oil to amortize the effort required to meet the requirements for the designation.
Here is what Dexos 2 requires: (from: https://360.lubrizol.com/Specifications/GM/GM-dexos2 )
Notice that Dexos 2 was intended for "advanced aftertreatment" aka catalytic converters and particulate filters in diesels. It is entirely for EPA requirements that GM NEEDS to meet to keep giving us big V8's. The reality is that many full synthetic oils meet these requirements already...there is an extensive list of oils that meet the requirements.
Mobil 1 just has a partnership with GM and Corvette, its the only reason they recommend it for fill. Anyone with an inkling of knowledge about oil understands that all oil, dino juice or synthetic comes from a "stock". The additives and blends are proprietary to each brand, but the base oil is typically shared across brands. Some brands specify a higher quality stock such as Motul which focuses on motorsport applications which demand more consistent and uniform oil degradation in extreme conditions, while Mobil 1 can and does use various grades of oil based on intended application.
The Motul 300V that I prefer to use is slightly more viscous than the Mobil 1 fill across the board, is less basic (less corrosive), and has better shear resistance, but doesn't meet the Dexos 2 metrics because it is a race lubricant and doesn't even offer Ash or Phosphorus content...because race car.
Oil is subjective and some people will swear by one or the other, and to be quite honest most Corvette owners would be suited with Walmart brand synthetic oil due to the intended use of the car being a daily driver and grocery getter and the need for high performance low weight oil is less necessary.
I'm rolling with the Mobil 1 fill on my future C8 because I am not going to do anything to jeopardize my warranty on the powertrain while I am making payments...once the warranty expires I'll see how the oil holds up over time with keeping results from https://www.oillab.com/ and seeing if I like them. If I feel like I would be better suited by returning to Motul then I will but I have a feeling that Mobil 1 will perform admirably since the specifications are very close to what I used with Motul. Also Mobil 1 is MUCH cheaper so the pocketbook may force my hand anyways.
As for the comment about trusting the engineers that designed the engine around a specific brand of oil...that is just silly. Engineers don't design to a specific brand, they design to tolerances and the lubricants that can allow them. As long as an oil meets the viscosity and shear requirements to allow those tolerances, that oil will perform just as well. The only unknown I see is how necessary Dexos 2 is for the cats, it seems odd because in high performance engines there is an extremely small amount of oil that makes it into the cat and I doubt that the cats on the C8 are so sensitive that a non Dexos 2 oil would cause any issue unless you were burning oil caused by poorly seated rings and that is a far more troublesome issue than dealing with cats.
Oil is oil for the most part, and true synthetics are without a doubt the best thing to happen to lubrication since...well...ever. The Dexos 2 nonsense is just another hoop that oil manufacturers have to jump through and certification they pay for to get the shiny new label. Mobil 1 and GM have a business arrangement and they put this Dexos 2 label on oil to amortize the effort required to meet the requirements for the designation.
Here is what Dexos 2 requires: (from: https://360.lubrizol.com/Specifications/GM/GM-dexos2 )
Notice that Dexos 2 was intended for "advanced aftertreatment" aka catalytic converters and particulate filters in diesels. It is entirely for EPA requirements that GM NEEDS to meet to keep giving us big V8's. The reality is that many full synthetic oils meet these requirements already...there is an extensive list of oils that meet the requirements.
Mobil 1 just has a partnership with GM and Corvette, its the only reason they recommend it for fill. Anyone with an inkling of knowledge about oil understands that all oil, dino juice or synthetic comes from a "stock". The additives and blends are proprietary to each brand, but the base oil is typically shared across brands. Some brands specify a higher quality stock such as Motul which focuses on motorsport applications which demand more consistent and uniform oil degradation in extreme conditions, while Mobil 1 can and does use various grades of oil based on intended application.
The Motul 300V that I prefer to use is slightly more viscous than the Mobil 1 fill across the board, is less basic (less corrosive), and has better shear resistance, but doesn't meet the Dexos 2 metrics because it is a race lubricant and doesn't even offer Ash or Phosphorus content...because race car.
Oil is subjective and some people will swear by one or the other, and to be quite honest most Corvette owners would be suited with Walmart brand synthetic oil due to the intended use of the car being a daily driver and grocery getter and the need for high performance low weight oil is less necessary.
I'm rolling with the Mobil 1 fill on my future C8 because I am not going to do anything to jeopardize my warranty on the powertrain while I am making payments...once the warranty expires I'll see how the oil holds up over time with keeping results from https://www.oillab.com/ and seeing if I like them. If I feel like I would be better suited by returning to Motul then I will but I have a feeling that Mobil 1 will perform admirably since the specifications are very close to what I used with Motul. Also Mobil 1 is MUCH cheaper so the pocketbook may force my hand anyways.
As for the comment about trusting the engineers that designed the engine around a specific brand of oil...that is just silly. Engineers don't design to a specific brand, they design to tolerances and the lubricants that can allow them. As long as an oil meets the viscosity and shear requirements to allow those tolerances, that oil will perform just as well. The only unknown I see is how necessary Dexos 2 is for the cats, it seems odd because in high performance engines there is an extremely small amount of oil that makes it into the cat and I doubt that the cats on the C8 are so sensitive that a non Dexos 2 oil would cause any issue unless you were burning oil caused by poorly seated rings and that is a far more troublesome issue than dealing with cats.
They design the engine. The oil company designs the oil to the spec the engineers tell them they want not the other way around. In many cases like BMW their BMW branded oil is made under contract by a specific oil company who then gets to put its logo on the fill cap. It was Castrol in the past & currently its Shell. IIRC Mobile also had a contract with them at one time.
Of course GM has a contact with Mobil. There are no car companies that don't have a contract with an oil company. First fills are a very big business.
Be interesting to hear exactly why someone needs to go with an oil not recommended for the car.
Last edited by BEAR-AvHistory; Oct 25, 2020 at 01:42 AM.
In recent years, Mobil and other main line oil suppliers have been following EPA directives and they have significantly reduced the Zinc and Phosphorous in their oils.
These two elements are important ingredients in oil for their anti-wear properties.
Just compare the amount of Zinc and Phosphorous in Mobil 1 versus Red Line or AMSOIL
I don't know enough about this subject to comment but here are some notes that I have accumulated.
CF corvettez51race As a former R&D engineer for one of the NASCAR and Rolex DP engine builders, I'll weigh in with the following:
1) Pro built engines can afford to run thinner oils because the bearing TOLERANCES are much tighter, so there isn't as much of a need of a "cushion" with oil viscosity. When I worked there, the aluminum block engines ran main clearances of 0.001" +/- 0.0001" (yes, one tenth of a thousand tolerance) when COLD. Hot were around 0.0023". We ran M1 5W-30 off the shelf (not the racing formulation)
2) We didn't run the racing formulation then because the EPA hadn't stepped in the way they have in the last couple of years.
3) The actual viscosity you want to run is a function of the bearing CLEARANCES and TOLERANCES - BOTH. In the GM LS engines, the cold clearances are tight, and tolerances are NOT. That's why 0W is preferred - to make sure you can FLOW oil and generate the wedge at startup and cold idle with tight, uneven clearances. Anyone who runs their engine HARD below about 160F oil is asking for problems on an aluminum block engine (or aluminum headed cammer), as the bearing clearances grow substantially from ambient to operating temps.
4) Purpose built racing engines are looking for every last repeatable HP. We spent an entire season looking for single digit gains. Adjusting the crankcase vacuum on a dry sump engine is worth power. It's that everlasting search for another 2-3 HP that has oil engineers on staff.
5) Most people in this thread are dealing with either stock or modified stock production engines, not pure race-built engines. As such, the rules of the game are a little different - make sure you have good (not insane, ie >70 psi) pressure at cold startup. At track temps, try to maintain solid pressure (40+ psi at redline). Big pressure dips in turns is bad, MK? Not OMG bad because typically the engine's not loaded, but it's not good for life. AND - if your oil temp exceeds ~280, change it after the event. I have yet to see an oil that retains a substantial amount of it's lubricity with constant exposure to those temps. As someone on here said, we're talking about a $70 (or more for the Z06/ZR1 guys) oil change, or a $6k+ engine.
At the end of the day, remember this: Pressure is good. A lot of pressure can be bad. High temps are bad. Cold temps and high load are just as bad. And probably the most important - if you track your car or drive it hard, your engine will not last forever. It's part of the "Tax" to play. The harder you run your engine, the better the oil you should run to maximize engine life.
Let's look a bit more in depth on why these 'micro brew' oils are so much better than say a normal Mobile 1.
Within the U.S. right now you may think you only have the choice of conventional and synthetic engine oils to choose from. While that is partially true the base stock that the oil is produced from can also radically change the properties of the oil itself, synthetic or not.
Within the Synthetic oils you have three classifications, Group 3, Group 4, and Group 5 oils. Group 3 oils are re-refined petroleum products and are the least expensive until recently they could not be classified as synthetic. Group 4 oils are PAO oils (Poly-Alpha-Olefine) and they are a synthesized petroleum product that has better protection against heat, oxidation, and better flow at low temperatures. The draw back to this oil is they need plenty of oil pressure to provide an effective protection film on the parts they protect. Both Group 3 and Group 4 oils are mineral based.
Lastly we have the Group 5 oils, which are Ester based (diester, polyoesters, and complex esters) which are vegetable and animal based
Red Line and Motul engine oils are currently the only two engine oils you can obtain that start from a Synthetic Ester base. This Ester base forms and electro-chemical bond with your engine components so there is an even less chance of metal to metal contact on cold start up or low oil pressure conditions. This bond is something that the Group 3 and Group 4 oils do not have because of their base material make up even if they have a higher level of ZDDP additives. The other big benefit of an Ester based oil is that they have very little in the way of deposits if they do burn under extreme conditions so there is no build up inside hot engine parts, and this is especially important for those running turbos on their cars.
Assuming you are willing to step away from GM's recommendation for dexos1 oil for a track day, I'd consider this:
The Z-ROD is near the top end of the 30 grade band, has lots of ZDDP, and is very similar to the AMSOI Dominator Racing 10w30 I use in my 02 Z06 at the track. But the Z-ROD has some detergent/dispersant and is good for about 3-5k mile oil change intervals (or one year whichever first) whereas I change the racing oil at about 500 mile intervals.
This assume an oil temp no hotter than 245-255F or so. Higher than that and I'd consider this: AMSOIL SAE Synthetic Premium Protection 10w40 (Product Code AMOQT) (zinc – 1378 ppm, phosphorus 1265 ppm)
I used this oil from about 04-07 when AMSOIL came out with their Dominator Racing line and I switched to the 10w30. With my oil cooler set and larger than stock radiator, my water temp is consistently below 220F and my oil temp is almost always 245-255F even in very hot weather.
STRONGLY recommended their 15W-50 if you're seeing 250 or higher temps. His primary focus was on shearing and the concern that after seeing temps consistently above 250 the standard 5W-30 may not thicken back up after cooling due to shearing.
There are two main issues with running Mobil 1 5w30 and you touched on one - viscosity. The other is anti-wear additives.
Viscosity.
The LSx engine was designed for an oil with a viscosity of about 10-11 cSt, which is what a 30 grade oil is at 212F - a 30 grade oil is defined as an oil having a cSt viscosity of 9.30-12.49 at 212F. At 300F, a typical 30 grade oil will have a viscosity of only about 30% of that value. Mobil 1 5w30 viscosity at 300F is 3.13.
There are two ways to address this. One, run a higher grade oil and two, add an oil cooler. The latter approach is the better option. A 50 grade oil has a viscosity of 16.30-21.89 cSt at 212F and typically has viscosities of 4-5 cSt at 300F, still well below that of a 30 grade at 212F, but about 33-66% higher than that of a 30 grade at 300F. Mobil 1 15w50 has a viscosity of 18 cSt at 212F and 4.5 at 300F.
But there are downsides to running an oil with that high of a viscosity including higher pumping losses, increased internal friction which drives up heat, and lower heat removal by the oil which also drives up heat.
A 40 grade seems to be a good compromise for a track day car without a cooler and maybe many that do have coolers. 40 grade oils have a viscosity of 12.50 - 16.29 cSt at 212F and typically have viscosities around 4 cSt at 300F. Mobil 1 0w40 has a viscosity of 13.5 cSt at 212F and 3.8 cSt at 300F. Due to their higher viscosity than a 30 grade, they will maintain film strength better at high temp high shear than a 30 grade and due to their lower viscosity than a 50 grade, they will have lower friction losses and will remove heat better than a 50 grade in typical heat ranges experienced by an LSx engine at the track.
Anti-wear Additives.
With the previous generation of oils, the API limited the amount of phosphorus in automotive oils to 800 ppm for 30 grade oils, down 20% from the previous generation and down 33% from the API SH spec which was in effect from 94-97. The API did this to prevent long term damage to the cats so the auto manufacturers could meet EPA requirements for 100k + mile emissions requirements as phosphorus carried through the exhaust due to oil burn off slowly builds up in the cats and minimizes their effectiveness. Unfortunately, phosphorus, along with zinc, in a compound called Zinc dialkyl dithio phosphate or ZDDP, form an oils main anti-wear additive.
So by running an off the shelf API SM 5w30 (as recommended by GM), you are running an oil with a viscosity too low for the track and one with much lower than historical anti-wear additives.
This oil does not meet GM owner's manual requirements, thus isn't recommend by AMSOIL which only recommends oils that meet the owner's manual requirements. But, it does provide more viscosity protection than a 30 grade with a viscosity of 4.3 cSt at 300F, almost has high as M1 15w50, has the proper detergents and dispersants for dual use track/street car, and has high levels of ZDDP (zinc – 1378 ppm, phosphorus 1265 ppm). Running an oil with a viscosity over that of a 30 grade will require an good oil warm-up. My personal thumb-rule is 150F before using high rpm or more than part throttle.
This oil runs high in the 30 grade band, just below that of a 40 grade and has a viscosity of 3.6 cSt at 300F. In my car, I get slightly lower oil temps running this oil over the 10w40 mentioned above with my oil temps at about 255F at Watkins Glen last summer in July. This is right at the top of where I feel comfortable with a 30 grade oil.
It also has very high levels of ZDDP (zinc – 1575 ppm, phosphorus 1474 ppm) - but like the 10w40 above, doesn't meet owner's manual requirements and unlike the 10w40 above has no detergents and no dispersants so isn't really a good option except for dedicated track day cars.
AMSOIL AMO 10w40 is not recommended for both the reasons you cite - viscosity too high (GM only recommends 30 grade) and ZDDP too high (GM only recommends oils meeting API specs for a 30 grade oil which limits ZDDP to 800 ppm), both of which are required to meet the older GM 4718M and new Dexos1 specs.
The AMO also has higher than normal levels of detergents and dispersants so you would be able to follow your normal routine. I did a series of used oil analysis tests in my 06 CTS-V daily driver which included a shift from Mobil 1 5w30 to AMSOIL 0w30 and on a fellow forum member's C5 which included a shift from CG 0w30 to AMSOIL 0w30 and back. Though the tests are somewhat dated and are different grades from the 10w40, they have similar levels of detergents and dispersants as the AMO 10w40. In both cases, the AMSOIL had higher levels of TBN than the other oils - thus you will likely see higher TBN on the AMO if you change your oil at the same point on the OLM.
This will somewhat simplistic, but illustrative of my concern. By mixing a 30 grade and a 50 grade you are combining "long" molecules (high viscosity) and "short" molecules (low viscosity) - the average will be something like a "medium" molecule - but that's not what you'll actually have. You'll have long and short. If I wanted a "medium", I'd use a "medium" (40 grade in this case) so all my molecules are the same size (assuming you are using synthetic). If I wanted something slighly over a "short", I'd still feel more comfortable mixing some "medium" with my "short" so they are closer in size. Thus if I wanted to blend my own 35 grade, I'd use half 30 grade and half 40 grade instead of 2/3 30 grade and 1/3 50 grade. My thoughts only.
Blue drain and yellow fish symbol used by the UK Environment Agency to raise awareness of the ecological impacts of contaminating surface drainageDue to its chemical composition, worldwide dispersion and effects on the environment, used motor oil is considered[by whom?] a serious environmental problem.[36][37] Most current motor-oil lubricants contain petroleum base stocks, which are toxic to the environment and difficult to dispose of after use.[38] Over 40% of the pollution in America's waterways is from used motor oil.[39] Used oil is considered[by whom?] the largest source of oil pollution in the U.S. harbors and waterways, at 1,460 ML (385×106 US gal) per year, mostly from improper disposal.[40] By far the greatest cause of motor-oil pollution in oceans comes from drains and urban street-runoff, much of it caused by improper disposal of engine oil.[41] One US gallon (3.8 l) of used oil can generate a 32,000 m2 (8 acres) slick on surface water, threatening fish, waterfowl and other aquatic life.[40] According to the U.S. EPA, films of oil on the surface of water prevent the replenishment of dissolved oxygen, impair photosynthetic processes, and block sunlight.[42] Toxic effects of used oil on freshwater and marine organisms vary, but significant long-term effects have been found[by whom?] at concentrations of 310 ppm in several freshwater fish species and as low as 1 ppm in marine life forms.[42] Motor oil can have an incredibly detrimental effect on the environment, particularly to plants that depend on healthy soil to grow. There are three main ways that motor oil affects plants:
contaminating water supplies
contaminating soil
poisoning plants
Used motor-oil dumped on land reduces soil productivity.[42] Improperly disposed used oil ends up in landfills, sewers, backyards, or storm drains where soil, groundwater and drinking water may become contaminated.[43]
Main article: Oil additiveIn addition to the viscosity index improvers, motor oil manufacturers often include other additives such as detergents and dispersants to help keep the engine clean by minimizing sludge buildup, corrosion inhibitors, and alkaline additives to neutralize acidic oxidation products of the oil. Most commercial oils have a minimal amount of zinc dialkyldithiophosphate as an anti-wear additive to protect contacting metal surfaces with zinc and other compounds in case of metal to metal contact. The quantity of zinc dialkyldithiophosphate is limited to minimize adverse effect on catalytic converters. Another aspect for after-treatment devices is the deposition of oil ash, which increases the exhaust back pressure and reduces fuel economy over time. The so-called "chemical box" limits today the concentrations of sulfur, ash and phosphorus (SAP).
There are other additives available commercially which can be added to the oil by the user for purported additional benefit. Some of these additives include:
Antiwear additives, like zinc dialkyldithiophosphate (ZDDP) and its alternatives due to phosphorus limits in some specifications. Calcium sulfonates additives are also added to protect motor oil from oxidative breakdown and to prevent the formation of sludge and varnish deposits. Both were the main basis of additive packages used by lubricant manufacturers up until the 1990s when the need for ashless additives arose. Main advantage was very low price and wide availability (sulfonates were originally waste byproducts). Currently there are ashless oil lubricants without these additives, which can only fulfill the qualities of the previous generation with more expensive basestock and more expensive organic or organometallic additive compounds. Some new oils are not formulated to provide the level of protection of previous generations to save manufacturing costs[citation needed].
Some molybdenum disulfide containing additives to lubricating oils are claimed to reduce friction, bond to metal, or have anti-wear properties. MoS2 particles can be shear-welded on steel surface and some engine components were even treated with MoS2 layer during manufacture, namely liners in engines. (Trabant for example).[34] They were used in World War II in flight engines and became commercial after World War II until the 1990s. They were commercialized in the 1970s (ELF ANTAR Molygraphite) and are today still available (Liqui Moly MoS2 10 W-40). Main disadvantage of molybdenum disulfide is anthracite black color, so oil treated with it is hard to distinguish from a soot filled engine oil with metal shavings from spun crankshaft bearing.[35]
In the 1980s and 1990s, additives with suspended PTFE particles were available, e.g., "Slick50," to consumers to increase motor oil's ability to coat and protect metal surfaces. There is controversy as to the actual effectiveness of these products, as they can coagulate and clog the oil filter and tiny oil passages in the engine. It is supposed to work under boundary lubricating conditions, which good engine designs tend to avoid anyway. Also, Teflon alone has little to no ability to firmly stick on a sheared surface, unlike molybdenum disulfide, for example.[citation needed]
Many patents proposed use perfluoropolymers to reduce friction between metal parts, such as PTFE (Teflon), or micronized PTFE. However, the application obstacle of PTFE is insolubility in lubricant oils. Their application is questionable and depends mainly on the engine design – one that can not maintain reasonable lubricating conditions might benefit, while properly designed engine with oil film thick enough would not see any difference. PTFE is a very soft material, thus its friction coefficient becomes worse than that of hardened steel-to-steel mating surfaces under common loads. PTFE is used in composition of sliding bearings where it improves lubrication under relatively light load until the oil pressure builds up to full hydrodynamic lubricating conditions.[citation needed]
A new process to break down polyethylene, a common plastic product found in many consumer containers, converts it into a paraffin-like wax with the correct molecular properties for conversion into a lubricant, avoiding the expensive Fischer–Tropsch process. The plastic is melted and then pumped into a furnace. The heat of the furnace breaks down the molecular chains of polyethylene into wax. Finally, the wax is subjected to a catalytic process that alters the wax's molecular structure, leaving a clear oil. [51]
Biodegradable motor oils based on esters or hydrocarbon-ester blends appeared in the 1990s followed by formulations beginning in 2000 which respond to the bio-no-tox-criteria of the European preparations directive (EC/1999/45).[52] This means, that they not only are biodegradable according to OECD 301x test methods, but also the aquatic toxicities (fish, algae, daphnia) are each above 100 mg/L.
Another class of base oils suited for engine oil are the polyalkylene glycols. They offer zero-ash, bio-no-tox properties, and lean burn characteristics.[53]
In recent years, Mobil and other main line oil suppliers have been following EPA directives and they have significantly reduced the Zinc and Phosphorous in their oils.
Interesting info. Particularly if using a flat tappet cam have to use something better than the oils available off-the shelf including a special break-in oil like offered by Joe Gibbs Racing. They have more Zinc etc that have been regulated out of todays off the shelf oil:
Joe Gibbs Racing Driven BR50 Break In 15w50 Oil
Used by Joe Gibbs Racing to break-in and dyno all their engines, this petroleum oil provides the highest levels of zinc and phosphorus for flat-tappet engines. The additive package promotes ring seal and provides maximum protection available for cams and lifters during initial break-in. Requires no additional additives. Viscosity typical of 15W-50.Proper Foundation For Maximum Durability & Performance
PS: Your posted comment, "Pro built engines can afford to run thinner oils because the bearing TOLERANCES are much tighter, so there isn't as much of a need of a "cushion" with oil viscosity."
Remined me of a comment made by Dale Inman, Richard Petty's Manger the 15+ years we sponsored them. When visiting the race shop while my folks were training etc, I asked him about the oil used and he responded with it's very light (a 00 type weight grade or some such low viscosity number) to gain maximum hp. I asked if that protects the engine? He responded with "for the 500 miles we need!"
Good post from another forum
Interesting info. Particularly if using a flat tappet cam have to use something better than the oils available off-the shelf including a special break-in oil like offered by Joe Gibbs Racing. They have more Zinc etc that have been regulated out of todays off the shelf oil: