Group III vs Group IV (PAO) Basestocks in the TDI Engine

Forget the SAE stuff, just ask the dudes at Jiffy-Lube what their cheapest oil is.

Which TDI engines were included in the test ?

Dieseldorf,

The CI-4 rated,PAO/Ester blends would include Delvac 1, Amsoil, and Redline Oil. The VW 505/ACEA B4 rated, PAO/Ester blends would include Mobil 1, 0w-40, along with synthetic oils from Lubemoly, Motul and some of the other smaller European oil manufacturers.

The Group III or Group III/IV blends in a 5w-40 weight - which fared poorly on this particular test - would include Petro Canada, Shell Rotella T, Chevron Delo 400 and Valvoline Premium Blue Extreme. Interestingly enough, the 5w-30 Group III oil in this test outperformed the 5w-40 Group III. The simple reason is that it contains a lower level of VI modifier. As a general rule, Group III oils will contain higher levels of VI modifiers than PAO based synthetics, since the VI of the basestock alone is significantly lower. A PAO based 5w-40 like Delvac 1 can be made with little or no VI modifier. This is why Delvac 1 is completely shear stable in actual use, whereas something like the Petro Canada 5w-40 can and does shear. As just one example, I recently ran some of the PC 5w-40 in my Audi 100, and it sheared down from 15.4 Cst to 12.85 Cst in 10,000 miles - you would never see that with Delvac 1, or the Amsoil Series 3000 for that matter.

what they are saying is that the pao based -40 have a problem with keeping soot in suspension..

and the additives are very very very very critical on the pao based oils..

not so on the group III oils... so they have to drop to a thinner oil to keep the deposits in line... and cant do it with a pao base -40...

so... if your run light duty and get rid of your car early.. go ahead and run the -30 and be happy..

if you plan to load it down.. run high temps and stress,, or keep it for 500,000 miles go with what the test prove..

"""Originally posted by SoTxBill:
how bout posting the one where the ran a fleet of cabs with the same additives,,, but only chagned the base.. they ran pao vrs group III...

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If that is the report I've read they found that the ideal oil for reduced wear and highest fuel economy was a group III/IV blend! the group III/IV blend beat out even the pure IV oil! ""

no its the test where the additives were kept exactly the same on only the bases were changed..

so that on the base oil charactoristics could be tested... scientifically... and the which exactly the same additives.. lots of rumors and wivestales were put to rest..

for you idiots out their,, NO,, you dont drive a cab... you know the gas engines that get 300,000 between overhauls, the ones that idle all day in traffic,, the ones that can put 10years of normal driving on an engine in 9 months... but you DO use oil, pistons, bearing and have scuffing, and piston ring cleanliness merit ratings...

you can twist anything to mean anything.. but if pao bases are so damn good,, how come they have to overload them the ep additives to get the wear to be the same as group III... how come they dont get a million miles out of fleet engines, how come with you run group III bases with the exact same additives as group IV bases the results are different that you claim.. how come pao x-40 have trouble keeping the pistons clean.. how come pao x-30 wear faster but get better mpg??

oops i forgot,, your diesel is special and requires the light duty oils that only give 150,000 miles of performance... vw 505 and acea b3/b4 oils (obviously you havent compare the acea "b" series test to the acea "e" series test or you would know the diff.. yes your running gasolene engine oil for the most part with lighter duty testing requirements.. )

your car,,your choice...

I have about $600,000 in engines and equip out there.. some of it at over 500,000 miles on the clocks... other than replacing a leaking valve cover gasket and an occasional injector pump every 150,000 miles... I KNOW what works...

yes, yes, your car is different,, it defies the laws of physics... like too slick said.. you WILL NOT be getting your engines to last pass 200k.. .. that you can take to the bank... my engines are already past 200,000.. and that I CAN take to the bank...

if you want high mpg.. run 0w-20

if you want your engine to last for 200,000 run 5w-40 or better yet run 15w-40 and it will last for 400,000...

it looks like the hd industry is doing a compromise.. and sb blend will give you a little of both worlds... that where the heavy duty industry is going... mean better mpg and still lowh wear and durability..

how the heck does cummins give a 500,000 mile warrantee... with 35,000 mile oil change intervals...

but no you go with the marketing hype.. go get a 500,000 mile waranttee garantee in writing and then come back to the table.. then i will listen..

i dont make this **** up,, i just read all the articles from all the manufactor's web sites... something that you should do..

you dont have to like it,, just dont lie about it..

additive solubility is something that isn't really well covered here(in this paper). and that T-Bill covered breifly.

Ted, nice discussion - keep up the good work. Slypup is keepin up the one liners

As for dieseldorf's comments: is Petro Canada 0W-30 a perfect oil? I think so

You get the enhanced additive solubility of the Group III, the cleanliness and benefits of having some PAO in there, some super fine basestocks. At a good price. Now will it protect and prevent total and complete wear? nah it aint perfect, but will it's benefits outweigh some of the weight issues? Yes I believe it does. Would I switch to the S2000? yeah I might - esp if I can get a handle on the increased soot loading with the bigger injectors.

I will say that fleet feedback from Coyne about the Petro Canada stuff is that using that super nice 15w-40 (extremely similar to the Delo 15W-40) is that fleet maintenace costs have dropped like crazy. But then anyone can understand going from a crappy Group I base like Delvac 1300 or Rotella T 15W-40 to a Group II (almost III) would do that.

I'm glad I had a chance to read that paper - its got some good discussion, there are a couple other older paper that look at low temp pumpability that i'm working on getting a hold of soon - I think they should have some very interesting data.

Originally posted by TooSlick:
Dieseldorf,

The CI-4 rated,PAO/Ester blends would include Delvac 1, Amsoil, and Redline Oil. The VW 505/ACEA B4 rated, PAO/Ester blends would include Mobil 1, 0w-40, along with synthetic oils from Lubemoly, Motul and some of the other smaller European oil manufacturers.

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<font size="2" face="Verdana, Helvetica, sans-serif">Ted, thanks, that's what I was trying to get at.

Also, are we now saying it's OK to use Mobil 1 0W-40 in our TDIs???

Couldn't you understand what Ted said the first time you quoted it? Three quotes and you are out!

Geoff,

The difference in performance between Group III and PAO basestocks in terms of ring sticking and/or high temp piston deposits is tied directly to how they thermally decompose at elevated temps. Any "impurities" in Group III basestocks, such as sulphur or more VI modifier, will result in the formation of very hard carbonaeous deposits on both the piston crowns and the ring grooves. Once formed, you will not remove these deposits simply by switching to Delvac 1. If that were the case, it would be no big deal.

While the referenced SAE paper did not specifically address the issue of high temp deposits in the turbocharger housing, I would expect the relative performance of Group III and PAO basestocks to hold there as well.

The earlier, '96-'97 Passat TDI's have shown evidence of this ring sticking/piston deposit problem - "Tomo366's" Passat comes to mind. These are engines that have run for a protracted length of time with Group II, 15w-40 petroleum diesel oils. I would put Group II and Group III basestocks in the same catagory when it comes to thermal decomposition.

Finally, Group III basestocks have the same solubility/seal swell issues as PAO's. That is precisely why they are typically formulated with 10%-15% ester basestock. Even the Group II petroleum oils require a difference additive mix than the older, Group I solvent refined basestocks. If you're really interested in this, I believe George Morrison at AVLube can give you more specifics.

I noticed with Delvac 1 the rating is CH-4,at least on the case I purchased a
couple of weeks ago. I noticed that there is no VW rating on it.

In checking with Mobil their Mobil 1 (0-40) meets all the VW specs. for TDI. I know
from this forum that Delvac 1 is the best oil you can use. But what I do not
undetstand is why it does not meet the VW specs.

Alster

Alster,

I'd estimate that 95%-99% of Delvac 1 is sold for use in commercial diesel engines. The TDI market in the US is much too small to care about - so why pay to test it?

The Mobil 1, 0w-40 is sold all over Europe for use in turbocharged, passenger car diesel engines. Hence it carries both the VW 505 and ACEA B3/B4 ratings.

Originally posted by TooSlick:
The Mobil 1, 0w-40 is sold all over Europe for use in turbocharged, passenger car diesel engines. Hence it carries both the VW 505 and ACEA B3/B4 ratings.

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<font size="2" face="Verdana, Helvetica, sans-serif">Ted, is the Euro Mobil 1 0w-40 identical to the product we can purchase in America?

hmmm the latest edition of high performance functional fluids doesn't mention anything about the issues you are bringing up. Almost sounds like you have an axe to gring with the Group III oils. . . .

The one thing that maybe needs to be pointed out is that under normal conditions the TDI does not get hot enough to cause these problems. Engine oil temps and engine temps themselves are related to load and RPM . . . This test was done at over 4000 RPM and full Load. Basically ya can't make the TDI work any harder. These conditions are well outside the spec of operation. That said it is nice to know that you have a solid level of protection esp if you want to beat up your engine like certain folks that saw 260 F sump temps!!!

As for the seal swell issues - this is also not brought up in any of the other publications I have come across. One of the advantages touted by Chevron and Petro Canada is that they can use the Group III in place of a PAO and not have to use an ester for seal compatibility issues.

While this could be most of these 'detractions' to group III oils are not supported in the literature I've read. Maybe I need to hit the books again

Guys...

Could the average Joe just simply offer a compromise of using a Group III oil and changing it in intervals of say 3,000- 5,000 miles?

In essence, would you still offer your TDI the protection it needs with the Group III oil with the 3,000 mile-5,000 mile oil change window?

I think it could be possible. What do you guys think about it? Is it feasible?

I change my Delvac-1 every 10,000 miles, and I pay attention to the oil level every time I head out onto the road. Being a teacher and a coach who drives a bus has trained me to do the Pre-Trip Inspection... GOOD Karma, eh?

Shawn

Geoff,

I have tried to keep an open mind when it comes to these Group III fluids....I do think they have their place as a midrange (and mid performance) product @ $10.00-$12.00/gallon. But in terms of extreme temp properties, viscosity index and impurities, they certainly are not PAO's. Here's a direct quote from the paper on TDI testing:

"In view of their favorable balance of volatility and viscosity, Group III basestocks are commonly used in Europe to formulate 5w-xx oils. These properties are generally intermediate between those of Group I and Group IV products as are their costs."

In other words, in Europe the Group III oils are considered a midrange oil, along with PAO/petroleum blends and are priced accordingly. All the top tier oils are and always have been PAO/Ester based.
FWIW, I do think these Group III oils are better suited to light duty diesel use than to high performance gas engines. Turbocharged gas engines tend to degrade the oil much more rapidly, with regards to oxidation/nitration and TBN depletion.

I'm not generating these SAE papers out of whole cloth BTW, I'm simply reporting test results that are in published and peer reviewed technical papers.

The Petro Canada 0w-30 does seem to be working well for you - however it does contain probably 20%-30% PAO to improve the high/low temp properties. I'm honestly not sure if a straight Group III based oil is going to perform as well in the long term. I haven't see any 0w-30 or 5w-30 diesel oils that didn't use a significant # of PAO. The Series 3000 is probably 80% PAO and 20% polyol ester. The new BP "Vanellus C8 Ultima", 5w-30 diesel oil is probably formulated along those lines as well. I expect it to be at least as expensive as Delvac 1 when it gets to the US and Canada.

nice read..

for you bone heads that cant read....

answer,, the 15w-40 passed with flying colors so there was no need to test farther.. matter fact is passed all tests first and foremost so it is the perfect oil for application requiring 15w-40 oil.. the piston merits are as good as any oil tested... especially if you add in the price,, then the question is why use anything else..

well there colder climates and increaseing fuel economy..

but even this article warns that you are very near exceeding the boundry layer with the thinner oils even pao based,, so your walking a tightrope.. trying to get better fuel economy but just stay away from going over the limit and destroying the engine.. thats why this is only used for LIGHT DUTY DIESELS!!!!!!(DUHHHHH!!!!)

it was when the group III were modified to create lower cold weather starting and economy that the dillution of the group III created a problem. then a mix of paos and group III turned out to be the best comprimise between boudry layer and fuel economy vrs price of the oil...

strange that this study doesnt look at the exsiting formulations that ALREADY have PASSED the test that are 5w-40 and already out there, instead of the oils it was working with..

go look at all the 5w-40 oils that are acea b4 and acea e4 (meaning they have already passed the di piston test) that are group III or blends of group III oils...

now when you go to 0w-xx oils especially 0w-30,, you better be grandma.. cause your too close to the boundry layer.. please stay up north and dont drive on warm days....

this is a long ways from heavy duty/servere driving conditions.. you right skypoop,, this IS a LIGHT DUTY engine.

[ December 17, 2002, 18:45: Message edited by: SoTxBill ]

its amazing that they read all the crap into the tests..... that threw out the "better" reference oil cause it showed no deterioration (the reference rl90 oil is 15w-40 group III) and use the lower testing 0w-30 oil... and if you read the tests, they are rather confusing in asmuch as they introduce oil sampls "e" "f" "g" and "h" in the middle of the test becuase samples a, b, c, and d were not giving them the results they wanted..(only "d" was showing some degradation, but not at the rate they wanted.. and they chose thier additive package and did not document what their additive package was... btw .. the test was by a company that makes additives, not base oils...

then they try to run an abbreviated test,, and found out the oils were too good for that to work...

and they base "good" on the acea b3 cec-l-78t-97 test.. a test that every group III oil sold in america has PASSED!!!!... not failed as their particular formulations did..
so what the heck were they trying to prove!!!!! that they dont know what the heck they are doing????

that they cant pass the test that all the oils over here do pass??? oh yea,, i forgot, you wimps are talking about LIGHT DUTY oils and engines...yea.. ok .. that right..your recommended oil are wimpy and dont pass like all of the HEAVY DUTY oils...

yea.. good test..showed YOUR oils are lousy,, mine are fine...

btw acea b3/4 oils are only rate cf here.. the oils i recommend are rated acea E5 and api CI-4...

no wonder your oils dont pass...especially if your playing with cf /b3 oils...

Geoff,

With regards to additive solubility ....

Here's a quote from page #32 in the December 2002 issue of "Lubes n' Greases" - a well known industry trade journal. The article is on "pour point depressant" additives used in Group II and Group III petroleum oils:

"Using additives typically employed for Group I oils in these mineral base oils may not always be successful, partly because the Group II and Group III oils have a very different composition and are less polar. This can make it difficult to dissolve standard additives into them. One alternative, wax-free PAO, offers excellent pour points - but it also has a price tag about four times that of mineral oils."

That's about as clear as can be, I think ....

TS

In hot climates, would not a 15W-40 and a 5W-40 perform equally?
From SoTxBill:

The 15w-40 passed with flying colors so there was no need to test farther.. matter fact is passed all tests first and foremost so it is the perfect oil for application requiring 15w-40 oil.. the piston merits are as good as any oil tested... especially if you add in the price,, then the question is why use anything else..
well there colder climates and increaseing fuel economy..

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<font size="2" face="Verdana, Helvetica, sans-serif">I currently use Delvac-1, but from reading all the above it looks like I should consider switching to either a 5W-30 (S3000) or a HD 15W-40. I can drive hard, and it is usually very hot down here. Any thoughts?

I think you nailed it.. if your NOT running a 15w-40.. THEN according to this test you need to be very very very careful.. as the 5w-40 and 0w-30 could cause ring sticking,,,

but if you research your oil before hand,, and the oil is truely acea b3 or E3 or higher, its already PASSED this test..

not just equivlent to.. but really passed the test these scientist were talking about.

the api ci-4 also has the equivlent test so again if the oil has really passed,,, your ok..

but it does show that 15w-40 is the perfect oil if you can live with the temp range.

oddly rotella recommends 40w can be used down to zero and then 15w-40 for HD applications below zero??????

The more I read, the more convinced I am that a good synthetic 15W-40 is the best compromise for my TDI. Especially given my southern (VA soon to be TX) location and lack of really cold starts due to a garage and a TDI Heater.

Pour point for the Amsoil HD 15W-40 is actually 4 degrees lower than the Shell Rotella 5W-40. And Noack is 6.7% for the Amsoil. At $20/gallon (I think), this seems like an ideal oil.

Tim

Mobil 1 15W-50
ACEA B3/B4-02 approved.
It's only API CF. (I change at 5k intervals because of city driving, so big deal.)
Pour Point -49F (same as Delvac)
Flash Point 491F.
Noack Volatility 5.5%.

$4.00 qt. at the local Target store.

Smokin,

I think that Delvac 1 is excellent to use, even if you live in Death Valley. The fact that it is almost 100% shear stable tells me it has little or no VI modifier in it to cause ring sticking. There is also the 25 year track record in commercial diesel engines to back that up ....

TS

Ted, just out of curiosity do you know the volatility numbers (NOACK %) of Amsoil's 10W-40 and Mobil's Delvac-1?

Fowvay,

Amsoils 10w-40 now comes in @ 6.6% weight loss in the Noack test ...the data I have on Delvac 1 is for the older CH-4 stuff and was 10%. In fairness to Delvac 1, the CH-4 formulation had a pour point of -65F, so they were using a thinner (lower molecular weight) basestock.
Based on the technical data for the CI-4 rated Delvac 1, I would expect the Noack to be a bit lower, simply because they appear to be using a slightly thicker basestock. This is a general trend I have seen with most of the CI-4 formulations - I suspect these are being biased to improve the high temp properties for use in EGR equpped, commercial diesel engines. These next generation engines are going to run hotter and cause the oil to degrade faster.

TooSlick

Thanks for the info. I have fed my TDI a steady diet of Delvac-1 for 80,000 miles and I was hoping to improve the cleanliness of my intercooler by reducing the amount of condensed oil vapors in the intercooler. I switched to Amsoil 10w-40 at the 90,000 mile mark hoping that this would help. I'll have to run it for quite a while to notice any difference. I was disappointed with the amount of vaporization that I noticed with the Delvac-1. I would add approximately 1 cup of oil (8oz) over the course of 10,000 miles which I attributed to boil-off. This oil was always found in the intercooler, just like the old wesson oil chicken fryer commercial. The oil went someplace and I was always able to find it. <img border="0" title="" alt="[Big Grin]" src="images/icons/grin.gif" />

I've been using Amsoil 10W-40 in both TDIs and never consume any oil, it is simply amazing.

Strictly from the standpoint of minimizing ring sticking and piston deposits and nothing else, the results of this paper would indicate that a "narrow range", PAO/Ester synthetic would work best. A narrow range synthetic would be something like a 10w-30 or 15w-40 grade. The further you deviate from this, say to a 0w-40/5w-50, the higher the level of piston deposits and/or ring sticking - all things being equal. So I think VW's recommendation to run a 5w-40 or 5w-30 synthetic oil year round makes perfect sense. VW/Audi are trying to maximize their corporate fuel efficiency numbers, hence they are recommending the thinnest oils they can get by with and still get acceptable engine life.

Ideally, VW/Audi would like to recommend 0w-30 or 0w-40 for maximum fuel efficiency, but it might result in slightly higher levels of piston deposits, so 5w-30/5w-40 is the best viscosity compromise they could come up with ....

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Re: Group III vs Group IV (PAO) Basestocks in the

I've been reading this to glean some info on which oil to use, both for my '85 Jetta, and my Dad's 02 TDI. The TDI only has 17k kms on it, yet I've notice significant smoke at cold/warm start, more than my '85 1.6NA with 260k kms! I'm wondering if the effects of stuck rings could appear at such low mileage? It has only been dealer serviced so far, so Castrol 5W40 I assume. I am planning to use Amsoil 15W50 full synthetic, or possibly Delvac 1300 in my '85. I'm thinking of getting my Dad to switch to the Amsoil also, since they are only in BC during the summer, and spend winters in Az. I know the TDI smoke at startup could be other things, but just wanted to ask if it's possible that ring sticking could occur so early. It's an automatic, so it has the larger pump/smaller injectors if this matters. I don't recall his '01 TDI 5sp having this problem, nor have I seen any startup smoke from 2 co-worker's TDIs...

Re: Group III vs Group IV (PAO) Basestocks in the

last week someone asked about the famous oil tests where when testing was done on vw engines...

and after reading the results..yes.. the 15w-40 oils were THROWN out due to showing NO wear...

so after reading all the hype.. sort through what the tests actually said.. but this is the one that used north american tdi engines and found out that only the pao based oils showed wear on vw engines..and had to rely on additives and mixes of qroup III oils...

after reading the tests COMPLETELY.. it was funny to see what it really said.. you can read it for yourself.. but follow the thread and follow the hype and bs...

As it turns out.. the same wear factors on big engines is proven to be the same wear factors on little engines... the tdi is no different.. all the magical myths are dispelled..

they do however get into the the differences of minor problems and talk about the desire to get more mpg vrs not increasing wear..

sorry but it took a while for me to dredge this up... and as you can see i have very little patietice for the hypers who cant read or have no facts...have fun..

Re: Group III vs Group IV (PAO) Basestocks in the

STBill, is the "15W40 argument" only a "wear vs no wear issue"? Why bother with 15W40 when you get better protection with a 5W40 oil, energy savings and superb cold flow properties? The auto and oil mfrs. are trying to simplify and reduce the number of choices the owner/operator must make. I don't view that as a conspiracy, I'm sure some do. /images/graemlins/rolleyes.gif

They're trying to make things easier, IMO, by unifying oil requirements.


Link to current VAG compliant-oils