Steve Snake Driver

Mobil oil re at Road Atlanta. Model year 19 oil factory fill is new 0-40 oil. Available Jan 19. Backward compatible for all years.

Marcho Polo

Have they said that this oil can be used for track time and we no longer have to change to 15-50? When they were at COTA in May, they indicated that they were working on a factory fill oil that could be left in for track days.

Steve Snake Driver

Yes that was primary reason for new oil. Also a correction - oil available in January 18.

JoesC5

0w40 full synthetic was the oil for Corvettes in Europe since 2005. It's also the recommended oil for my Mercedes.

Many of us(myself included) have been using it for years. Presently, I have 30 quarts of the 0w40 European Car Formula oil in my basement, and another 10 quarts on order( to take advantage of the rebate from Mobil currently going on until Oct 31, 2017).

Never a problem using it in my C6 Z06 at 7,000 RPM.

Gonzo

Good info thank you both !

Kent1999

Sounds like a good change.

Is there any official doc/statement on this that I can print out and keep in my folder in case there’s every a warranty question? (Yeah, I know, but I’m just funny that way.)

rmorin1249

Anyone know if Walmart sells the 0w40?

JoesC5

yes they do. $22.88 for a 5 quart jug. Mobil has a rebate on them through Oct 31, 2017 and get $12 back. You can buy two jugs and get $24 rebate.

JHundertmark

#7&8 - Qualified yes - At least Walmart in Southeast Michigan had 0w40 in August of this year. Your results could vary depending on your store & timing.


Good luck

LDB

That’s not correct. Look on a European Chevy site like Chevrolet.uk, and you’ll find the same recommendations as the US, 5W30 street, 15W50 track. There is no mention of 0W40 by GM or Chevy in Europe. That said, it is true that some European manufacturers such as Mercedes and BMW do recommend 0W40. Since it is more accepted over there, it is entirely possible that dealers over there use it. But Chevy does not recommend it.

The advantages of 0W40 are obvious. It’s better on both the hot and cold end of the oil temperature scale. The disadvantage is that to achieve it, you must use VI improver additive even with a full synthetic. A full synthetic can achieve 5W30 without VI improver. Historically, VI improver additives are not very stable, and if they degrade, you lose viscosity on the high end. So a full synthetic 0W40 could degrade to 0W25. Of course the oils are basically the same in the US and Europe, so why would some European makes recommend it while US makes do not? Easy. They just view tradeoffs and risks differently. The 0W40 is somewhat better in most respects, but somewhat riskier in VI improver stability.

When I retired 7 years ago, I would certainly not have trusted viscosity of a 0W40 to hold up much past 3000-4000 miles, if that much. Neither would GM, which is why they didn’t recommend wide spread oils. Of course, additives are always improving, so it’s possible VI improver is now robust enough for normal oil change intervals. But I wouldn’t trust it for normal, 10,000 mile use until I saw it recommended for that use in an official GM publication. The fact that Mercedes and BMW recommend it for some applications would not convince me, because they were recommending it back when I know for a fact that it was risky. But if GM now changes their mind and says it’s ok in print issued by corporate GM (not a dealer), then I would assume there’s been enough improvement in VI improver additive since I retired to make it ok.

Note that none of the above concerns apply if you are a frequent oil changer. I wouldn't have had any concerns even 7 years ago going 3000-4000 miles on 0W40 full synthetic.

rmorin1249

Thanks.

Patman

I've been using M1 0w40 in my wife's BMW for years now, but the problem I have with it is that after the oil thins out in the first few thousand miles, then it actually ends up thickening up, and quite a lot too. Her oil analysis results usually show that the 0w40 has thickened up to almost a 50 weight oil. IMO that is too thick for most C7s, especially if you're not driving it all that hard.

cargun

I'm expecting this to be a NEW 0w40, not the 0w40 that's currently on the market. Looking forward to seeing it. Will probably run it in the LS's too, but really interested in it for the LT1 due to unique challenges DI places on the oil. Just had my last free oil change and the first one I do myself will be Jan/Feb timeframe.

village idiot

Good to know. I'll be out of the country for a month- I think I can last till then to get it done for free at the dealership.

JoesC5

Mobil recommended 0w40 as I don't believe that 5w30 full synthetic was readily available in 2005 in Europe'

I'm sure BMW and Mercedes have extensive engineering knowledge about oils and would not be specifying 0w40 if they believed it was detrimental to their engines.

Back in 1999, Mercedes stated that the normal oil change frequency was 1 year or 10,000 miles(whichever came first) using fully synthetic 0w40 oil, not 3,000-4,000 miles as you think is only acceptable. They must think that the VI improver is robust enough in Mobil1 0w40 as Mobil1 is on their list of approved oils to maintain their warranty.








GM and Mobil have a long history of working together and I really doubt that Mobil would be stating that it is okay to use their Mobil1 0w40 in the Corvette without GM's approval. Read the brochure where Mobil states several times that "Corvette recommends Mobil 1 0w40".

LDB

As I said in post #10, VI improvers may have gotten more robust in the 7 years since I retired, and if they have, GM may be in the process of changing their mind by approving 0W40 for general use. As you say, it seems unlikely that Mobil would claim Chevy recommends it unless it’s true. But I still haven’t seen it in print from Chevy or GM, so there’s at least some room for doubt. For example, a possible way of interpreting things is that GM thinks it’s ok for track use because cars used at the track tend to change oil much more often. So does GM now think 0W40 is OK for routine use to 10,000 miles? While I’m not sure their answer is still no, I won’t be confident that it has changed to yes until or unless I see it in print from them.

As to Mercedes and BMW recommendations for 10,000 mile 0W40 several years ago, your statement is of course correct in a narrow sense. They certainly wouldn’t have recommended it if they didn’t think it was OK. But as also pointed out in post #10, there’s room for honest disagreement. I saw plenty of data from before my 2010 retirement that showed 40 spread oils were risky for 10,000 mile change intervals at that time. I’m not talking high risk of massive failure. I’m talking pretty good chance that by 10,000 miles, the 0W40 would be 0W25. What keeps that from being a massive risk is that even if it does degrade that far, your engine isn’t at high risk of short term failure. It just isn’t as safe.

I don’t think we’re in gravely serious disagreement. I’ve just lived through the horrors of early VI improver fiascoes in the 1970’s and 80’s, and though they were vastly more stable by my 2010 retirement, they still weren’t fully robust at that time. Are they now? Maybe. But maybe not. That’s why to make me believe it with high confidence, since I don’t see actual data any more in retirement, I’d need to see it in print from somebody like GM who had been, like me, unconvinced that they were ok for long life use.

Patman

I also have to ask the people on here, why would YOU want to use 0w40 in your Corvette? I understand the hard core track guys will want to use it, because with the elevated oil temps you will see, having the thicker oil is beneficial especially when you consider that a 40 weight oil at 250 degrees is probably similar in viscosity to that of a 30 weight oil at 200 degrees. And if you can run that same oil not only on the street but on the track, it's a time saver, you no longer need to switch back and forth between 15w50 and 5w30 anymore.

But for those that just drive strictly on the street, and only see normal oil temps of around 200 degrees, it's not really necessary, you will already see long engine life from 5w30.

DWS44

I was wondering that myself. If only street driven, is there any advantage to switching to the new 0w40 or best to stay at 5w30?

RMS73

JoesC5 post says Mobil recommends 0w40 Mobil oil not GM. I doubt that Mobil would cover the engine failure. Obviously GM would not cover the engine since you are not using the GM recommended oil.

JoesC5

I suggest that you re-read my post. The Mobil brochure also says that "Corvette recommends 0w40 Mobil 1". I suggest you carefully read the Mobil brochure I posted.

GM in fact did warrant the Corvette in Europe where they recommended using Mobil1 0w40.