What is the best synthetic oil? Best oil filter?

[kck]

In an earlier post regarding the best synthetic oil, Gary Wells has noted that the GM adds a supplement to the factory-installed Mobil 1 engine oil; specifically, GM EOS (engine oil supplement). Furthermore, although I cannot find a clear statement in the GM 2009 Owner’s Manual for the mileage between oil changes that the company recommends for the V, some forum members appear to suggest that GM has a recommendation of 5,000 miles.

This leads me to the following question: If GM assumes that their “break-in” supplement for the engine oil will be present for at least the first 5,000 miles of engine life, would it not be wise to use this GM EOS supplement with any oil changes one does until the V reaches the 5,000 mile mark?

Kyle

[Gary Wells]

I don't believe that GM claims to use a specific or specialized "break-in engine oil" process anymore. However, you might want to do some research on this subject. Google GM EOS, Engine Oil Supplement, Richard Clark, ZDDP+, ZDDP, and so forth. I do believe that GM uses a lot of EOS, or something similar that is heavy in concentration of Zinc for their engine assembly, at least for the ZO6's. It has been reported that an independent oil analysis was done on a original 1st oil change coming out of a ZO6 and it contained somewhere in excess of 3000 PPM of Zinc, I believe. Considerably higher that found in any "legal" street oil on the market today. HTH

[C66 Racing]

Kyle,
Appreciate the kind words. I really do appreciate the dialogue with guys like Dallara and work hard to clearly separate my opinions from more factual info.

That said, here are some opinions. I've been a long time member of several Corvette Forums (bought my Z06 in Aug 01) and I do not remember seeing what I consider concrete info on any break-in additive used in LSx engines by GM. I am confident that in the Corvette and my CTS-V (V1) there is no mileage recommendation, even for the first oil change. GM strongly advises to follow the OLM. Additionally, your post is the first I remember reading about a coating on the ring/pinion.

Over the past four years or so, I've seen several articles put out by AMSOIL indicating that early diff fluid changes help prevent long term wear similar to this one:
Change Gear Lube after Break-in for Long Differential Life

My general practice has been to change all the factory fluids out at about 1000 miles, which is what I did with my Z06 way back when. My CTS-V was a little different as I bought it as a used corporate car with about 7k miles on it, but I still changed out all the fluids not too long after I bought it.

[Dallara]

~


Threads like this are always fun, that is as long as everybody realizes that there can never really be one absolute and finite answer. There are simply too many variables, and especially complete unknowns. All any of us can really do is read a lot, think a lot, and make our own decisions based on our own interpretations of all the data involved. It's been an enjoyable dialogue with C66, along with others, and there's really no reason threads like thsi can't be cool and civil.

Regarding additives, and in particular engine oil additives...

Our illustrious federal government - specifically the Environmental Protection Agency, or EPA - in it's wonderfully infinite wisdom has mandated that one of the most effective oil additives against engine wear, zinc dialkydithophosphate, or ZDDP, has to be eliminated from all automotive motor oils due to ZDDP's possible harmful effects on emissions control systems.

ZDDP has often been thought of as a "break-in" lubricant, but one has to ask the question if it indeed had only been a "break-in" speciifc component then why did literally all auto engine oils have it as an essential part of their formula for decades? ZDDP essentially puts a layer of zinc phosphate between metal components and prevents them for coming into contact with each other. Most engiine "assembly lubes" contain a ton of zinc for this very reason.

There is a huge amount of debate out there as to whether or not the removal of ZDDP is going to cause engine wear issues down the road, but I haven't seen any hard data anywhere regarding the effect of the removal of ZDDP and high-mileage modern engines. Maybe Google can be of some help here, but no doubt you will have to sift through a lot of conflicting information.

If you are interested in adding back the ZDDP to your oil that the EPA has decided to have removed for you it's really not a problem. Companies like Lucas and Redline both make ZDDP additives readily available at just about any auto parts store. Just look for "Break In Oil Additive" from either one. I am sure there are other brands of ZDDP additives out there, but I have used both those two and know how easy they are to find. They are neither one very expensive, either.

Here's an interesting info page on ZDDP...

http://www.ttalk.info/Zddp.htm

Hope this helps!

Dallara



~

[kck]

Gary, Brad, and Dallara: Thanks to you all for your very informative feedback on my three posts. I’ll definitely research the links you have kindly provided, and get back to you, if I have any questions.

I was hoping that Short-Throw might see this thread and elaborate some more on the “coating” he described for the ring and pinion in GM differentials. I would send him a private message, but I apparently do not have the necessary forum “privileges” to do so.

I was wondering if any one of you has an opinion on whether the (slightly) lower viscosity for the “start-up” value for the 0w30 Amsoil would have any “real-world” benefit compared to the 5w30 for Mobil 1? As far as I can tell, there is no car engine oil that has an upper (hot) viscosity of at least 30w that also has anything lower than 0w for start-up. Is that correct?

Also, do you have an opinion on whether using EOS (break-in) fluid might hinder piston ring sealing – or is that no longer an issue with modern car engines? Indeed, one forum member posted a link to an article (at “mototuneusa”) suggesting that modern engines should be broken in “very hard” initially to facilitate this ring sealing process. But if this were true, it would seem to require that one would have to ignore GM advice regarding the “gentle break-in” period for the differential and transmission.

Kyle

[CadillacSTS2003]

another vote for German Castrol

[marktanner]

Porsche specifies Mobil 1 0-40 for it's engines. Wouldn't that spec be beneficial for our engines, too? Are there any disadvantages to using oil with these specs?

[Gary Wells]

Kyle:
I would recommend doing a lot of research on any oil additive on new cars before you take the plunge. Most peeps running GM EOS, ZDDP, ZDDP+, & any other product designed as an anti-scuff agent are running flat tappet cams, which were common in the '80's, but have been replaced by modern camshafts & valve train components such as rollers which most peeps do not believe requires an anti-scuff agent. Research Richard Clark who designed & manufactures the product ZDDP+ as he has done quite a lot of research on oils & lubricants. GM EOS & so froth could be harmful to your cats & might shorten their lifespan. HTH & only my $.02 worth.

[Dallara]

~

Originally Posted by kck

I was wondering if any one of you has an opinion on whether the (slightly) lower viscosity for the “start-up” value for the 0w30 Amsoil would have any “real-world” benefit compared to the 5w30 for Mobil 1? As far as I can tell, there is no car engine oil that has an upper (hot) viscosity of at least 30w that also has anything lower than 0w for start-up. Is that correct?

Also, do you have an opinion on whether using EOS (break-in) fluid might hinder piston ring sealing...

First off, Kyle, you are more than welcome for any info I can provide you think is of some help. After all, we're all just wanderers in the desert, thirsting for information. I wish I knew where the oasis of all knowledge was, but all I can do is wander from well to watering hole and hope I don't make too many mistakes...

Before offering up my thoughts on your viscosity question let me first state - I think both Amsoil and Mobil 1 are fine products, and have used them both extensively. I would not hesitate to use either one with complete confidence that my engine would be well protected.

That said, IMHO there are absolutely no discernible benefits - or drawbacks - between a 0W-30 or a 5W-30 during "start-up" regardless of the temperature. Both oils, again IMHO, will flow equally well at "start-up" and both have vastly superior film strength to remained adhered to engine surfaces enough to be there when you first crank the engine over.

Try to remember that the recent trend toward lower (and zero) weight oils has more to with trying to get better efficiency and reducing pumping losses than it is for engine protection at "start-up". Zero viscosity - or "water weight oil" as we used to call it around the race teams - was used there to allow ultra-high pressure deliveries and friction reduction more than anything else. Any of the modern low-vis oils will do a fine job of protecting your engine during cranking, no problem.

Regarding break-in... Funny thing how there seems to be as many opinions and ideas about that as there are about oils!!!

Personally I tend to believe an approach that leans toward being fairly gentle early, yet with with occasional bursts at full throttle all the way through the gears is the best way to go. Regardless of modern materials all engines need some max cylinder pressures to achieve good ring seating, but that certainly doesn't mean the entire driveline needs to be subjected to hammer-and-tongs launches and banzai runs all the time. I tend to believe good, gentle, sufficient warm-up at all times, followed by a measured and smooth driving style for the most part, but with a once or twice daily full throttle roll-on through the gears is a good and reliable way to properly break-in a modern street car engine. Do this for 500, 1,000, 0r 2,000 miles... Whatever YOU feel most comfortable with - after all it's YOUR engine - and then drive it however you feel best after that. Modern street car engines are pretty tough hombres, and with just a modicum of care and good sense they will last an amazingly long time. With dedicated and discerning care, proper maintenance, high quality support fluids and fuel, etc. they will last literally forever without ever having to be opened up. Modifications can change that, to be sure, but if left stock they truly do border on unbreakable these days.

Wiil EOS, ZDDP, or other additives hinder ring seating?

Who really knows? Some say it can, while others say it actually helps.

Geez, I still come from the mindset that I will not run a synthetic oil in any of my motorcycle engines until they have at least 3,000 miles on them, and with some brand bikes not until they have 6,000 miles on 'em!!! Until then it is good ol' dino oil...

But that's another subject entirely...

With my Chevy trucks I used dino oil in 'em for the first two oil changes, then I switched to synthetics. Yet with my last three "performance" cars - a Merc-Benz E500 followed by a Jeep SRT8 and now the CTS-V - I started with Mobil 1 synthetic from the get-go and stuck with it, primarily because that's what each manufacturer recommended.

Doesn't make much sense, I know... I guess I'm just the "Ty Webb" of the motor vehicle world.

My best advice... Do what feels right to you.

Hope some of this helps!

Dallara




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[SlvrBullIT]

Good thoughts Dallara. /agree on everything you said, but alas I'm clueless on motorcycles so I trust your judgment on non-synthetic until a certain point.

[C66 Racing]

Originally Posted by marktanner

Porsche specifies Mobil 1 0-40 for it's engines. Wouldn't that spec be beneficial for our engines, too? Are there any disadvantages to using oil with these specs?

Interestingly, GM also specs the Mobil 1 0w40 for the Euro Spec Corvette Z06. I suspect that if not for CAFE (and the EPA), they'd spec it for their U.S. market LSx engines as well.

I'd argue that the 0w40 is better for your engines that any 30 grade and that is why I have used a 10w40 in my 02 Z06 on the track for many seasons. But, the disadvantage is that the owner's manual specs a 30 grade oil, so if you use a 40 grade you are really on the fringes of your warranty coverage.

Commenting a little deeper on Dallara's comments on ZDDP above, the current API SM/ILSAC GF-4 spec for phosphorus is 800 ppm. Top 30 grade oils like AMSOIL 0w30 and German Castrol used to have zinc and phosphorus on the order of 1000-1200 ppm.

As to the wear of the newer API SM/ILSAC GF-4 oils, they seem to be doing well in my V1 as compared to the labs universal averages for this engine family:
Cadillac CTS-V Used Oil Analysis – Mobil 1 5w30 & AMSOIL 0w30

Finally, for those willing to step outside the owner's manual requirements, there are oils that still contain high levels of ZDDP on the market and AMSOIL makes several including these two with phosphorus on the order of 1265 ppm and zinc on the order of 1378 ppm:
AMSOIL Series 3000 Synthetic 5w30 Heavy Duty Diesel Oil
AMSOIL SAE Synthetic Premium Protection 10w40

Mobil also makes several oils with higher ZDDP than the API SM 30 grade oils. You can see how much phosphorus and zinc are in various Mobil oils here:
http://www.mobiloil.com/USA-English/...duct_Guide.pdf

[Gary Wells]

Only an observation, but I notice that the revision updates on one of those infos is 03/06, without a year. Please don't shoot the messenger on this.

[kck]

Wow!! I’m an “information junky” and you guys have provided abundant information so as to delight my heart. But given how big the car industry is (and the huge amount of research dollars they have available), it is staggering to realize that that there apparently have been no definitive empirical tests regarding the engine oil issues you guys discuss.

Gary: I’m sorry I am so dense on this topic, but I’m struggling to reconcile your two posts to me (which I really appreciate you taking the time to do). In the first one you seem to suggest that GM includes considerable factory-installed EOS-type additives in their Z06 engines – which would lead me to include a pint or so of GM EOS in all the engine oil changes I do for my (Vette-based) V engine, especially for the first two or so oil changes during the “break-in” period. But then in your second post to me, I get the impression that you are concerned that the EOS supplement (and its high Zinc content) might damage the CATS. However, if that is true, then why would GM use EOS in their Z06 engines? You also note that modern camshafts & valve trains do not need EOS. So, in your first post regarding the E0S that GM puts in the Z06, did you possibly mean that GM used to put EOS in the older-style Z06 engines, but now GM does not include EOS their current (more modern) Z06 engines?

Marktanner: I was not aware that Mobil 1 had a 0w40 product. And based on my admittedly not very knowledgeable background, I would certainly share your reaction that this oil would seem to provide both the best start-up and race-level performance characteristics – and now knowing that Porsche recommends it would seem another point in its favor. It’s also very interesting, as Brad reports in his post, that 0w40 Mobil 1 is the “Euro Spec” for the Z06. (And Brad’s PDF link for Mobil 1 products shows that the 0w40 formula is also the Dodge Viper spec, and that it has 1100 ppm Zinc content vs. the 900 ppm for the 5w30 Mobil 1.) Am I correct to assume that the European and U.S. versions of the Z06 engines are essentially the same?

Brad also notes, however, that the Owner’s Manual for the V would suggest that using 40 weight oil might place you on the “fringes of your warranty coverage.” Indeed, the manual recommends 5w30. So the “0” (“start-up”) weight grades of oil might also be in apparent violation. But my interpretation of the manual indicates to me that GM is OK with any oil that meets a certain “numbered” spec (the exact “numbers” of which I do not have in front of me), regardless of viscosity range. And it’s my understanding that all the various synthetic oils we have been discussing meet this “numbered” spec.

Is it possible that that GM might be concerned that the 40 weight engine oil would be “too thick” when hot? But then it would not seem to make any sense to me that 0 weight oils could be “too thin” when cold (i.e., at start-up). And, to repeat an earlier point, why would GM specify 0w40 Mobil 1 in their European Z06?

Dallara: I was following Short-Throw’s advise (which appears backed up by at least some empirical evidence) that one should adhere to GM’s recommendation to break-in the differential very carefully by not engaging in any full-throttle runs for at least the first 500 miles (and no speeds exceeding 70 mph for the first 1500 miles). Now your comments to do (at least limited) WOT even during the break-in period (in order to better seat the piston rings) has me worried that I’ve been “way to gentle” in the 350 miles that I have driven my V so far. (Until I read your post, I had dismissed an article I’d read that said you should run your engine really hard in the first 20 or so miles… or you will never get the rings to seal properly.) As I implied in my earlier comments, I’m really becoming “torn” over the lack of consensus on these “break-in” issues!! (And I really like your analogy regarding your never-ending quest for the “oasis of all knowledge.”)

Kyle

[C66 Racing]

Gary,
I think you are referring to the 5w30 Heavy Duty Diesel as being labeled as an 03/06 data sheet - mostly means I haven't updated that page of my dealer website recently... the actual phorphorus and zinc levels I posted above are from a very recent AMSOIL Tech Bulletin to its dealers on oils with high ZDDP that are suitable for flat tappet cam engines. Short story - those ZDDP levels are current.

Kyle,
Go to a Corvette forum and search for answers to your questions and you'll find that this is a frequently debated topic. I'm not sure we'll ever really know how best to break in these cars. I now break in my LS6 engines in my Z06 by putting them in the car and going racing.

In answer to your questions on the 0w40, it is my opinion that GM specs them for their European models because it is a better oil for the engine. I believe that they sacrifice that better oil for one that isn't as good to improve their overall CAFE rating. For the same reason Ford has gone to 20 grade oils and most auto manufacturers have dropped the viscosity in their tranny and diff fluids. Their warranties only have to last 100k miles and they are balancing a trade off between improved fuel mileage numbers for their fleet against engine failures. For me, I want the best. Unfortunately, the owner's manual specifies an oil meeting GM Standard 4718M. To meet that standard, the oil must be a 30 grade oil (note that several 0w30s are labeled to meet this standard). Thus, 40 grade oils are out. If you want to use a 40 grade oil which has the dual benefit of a higher hot viscosity (as compared to a 30 grade) and a higher ZDDP, you can't comply with the owner's manual. Bummer. Thus I use what I feel is the best API SM, GM Standard 4718M oil for my V1, the AMSOIL Signature Series 0w30. For my track Corvette, the owner's manual went out the window years ago and I use oils very high in ZDDP that don't meet GM Standard 4718M.

[marktanner]

I also think the 0-40 is a better oil, which is why I asked about it. I especially think it's hot weather capabilities could be important in the summer while running hard with these blown engines. Does anyone really think that a dealership or even GM could tell the difference between 5W30 and 0W40 without an expensive analysis, especially if the oil was used for a few thousand miles? I don't. Usually they only worry that at least minimum spec is met, and don't mind if you purchase additional protection. Another reason that GM may have spec'd the lesser grade oil is that 0W40 is not that readily available; I had to get mine at the Porsche dealer. It's interesting to note that Porsche also specs two years or 30,000 miles for an oil change for the GT3, even under severe duty (and I verified it at the factory). They must be quite confident in that oil!