dn0z

I have a 2015 Z06/07.I know this subject has been discussed over and over but I'm still at a loss to understand. I spoke with several dealers and each said they use Dexos and if I want Mobil 1 oil, that its not part of the car program. If I want it I have to pay. Paying is not the real issue for me. What is the recommended or best oil for this engine. Should dealers use Mobil 1 or Dexos on oil changes. Thanks in advance.

BOBSZ06

Print this and give it to the dealer....Mobil 1 it is.

JoesC5

In addition, Mobil1 5w30 is dexos approved.

Is it any wonder that no one wants to trust their $100k Corvette to a dealer for something as simple as an oil change, much less letting them do any repairs to the car(even when it's under warranty).

TEXHAWK0

Dexos is a GM spec, not an oil brand.
Mobil 1 meets the Dexos spec. but so does the GM blend and dozens of other oils.
Mobil 1 may be preferred by owner, but not required (in the owner's manual).
I actually prefer another synthetic, other than Mobil 1.

dn0z

Thank you very much. This is the most definitive I've seen

fdxpilot

Not according to the bulletin above. Free oil changes are supposed to be Mobil 1. If you're paying, put in what you want.

s_c5519

For starters, thank you, and this needs a bump. I wish I would have read this first before I went in for my 500 oil change today.

The dealer asked me if I wanted Dexos which the car came with from the factory at no extra charge, or Mobil 1 for an additional $55.

I was a bit confused between the two and asked what's the difference and he said Dextos was a blend, not a full synthetic.

I am guessing the car will be fine until the next oil change with the blend, or should I go back and have them put Mobil 1 in it?

Also does the Z06 come with Mobil 1 for the break in oil or is it a blend?

mdz06vetter

As mentioned Mobil 1 is a BRAND of oil - and it meets the DEXOS spec for the current Corvette as designed by GM

Specifically designed to meet the needs of GM gasoline engines, dexos1™. The products that are listed on GM's web site as licensed by GM are as follows:
ExxonMobil Mobil 1 5W-30
(Shell) Quaker State Ultimate Durability Full Synthetic 5W-30
(Shell) Pennzoil Platinum Full Synthetic 5W-30
Smitty's Supply Incorporated SureGuard dexos1™ SAE 5W30
Smitty's Supply Incorporated Super S dexos1™ SAE 5W-30

JoesC5

Your list left off most of the 'full Synthetic" oils that meet the dexos spec. I also see that Royal Purple is now on the list.

http://www.centerforqa.com/gm/dexos1-brands

dar02081961

As I understand it even though the filler cap does not have the Mobil 1 label on it anymore, Mobil 1 is still the Corvette factory fill oil.

As others have stated Mobil 1 meets (actually exceeds) the GM "Dexos" standard. The Dexos standard is met by many synthetic blends and full synthetics other than Mobil 1. There are at least 15 or 20 choices out there.

I wouldn't use anything less than a full synthetic regardless.
And if it's hot where you run, I would use a viscosity greater than 5W-30 which was a fuel mileage formula from the start.

But to each his own.

AORoads

Not being nasty, but you guys who've been on here a couple months or a couple of years, I wish you had read it, too. There is not a week that goes by that some piece of important info is not on CF. Some is repeated, over and over and over. So, I think it's fairly safe for me to say that just about 2-4 times per month, there is an oil thread started. And there is also the search function in the red bar above. So please: stop in, read, and then go do whatever else you need to do. Good luck with your cars.

mdz06vetter

With that being said - what about a STICKIE for all the same regurgitation every so often!? Just saying..........

xp800

Your dealer is out of date by about 4 months. This lack of awareness at the dealership level for the use of ONLY Mobil1 5w-30 oil for ALL C7 is rampant unfortunately. You would be well within your rights to go back and request they fix their mistake and fill with Mobil1. I'd imagine you will get a pretty good push back, so be prepared with the documentation. Also have the service manager call the 800 number to hear for himself. But the GM dexos blend they put in is realistically more than fine for most uses short of track events or extreme conditions. What it's worth and any peace of mind is your call.

If you are charged, you can get reimbursed by calling the number at the bottom of the document.

The document posted above has been referenced hundreds of times, and supersedes the owners manual (until a new printing).

Mobil1 is the factory fill.

The thread of the shenanigans on Mobil1 use is ongoing in General:

https://www.corvetteforum.com/forums...-use-only.html

xp800

There is a sticky in C7 General as I mentioned above. But few Z06 owners take the time to look... I have PM'd the mods suggesting cross posting some of the stickies to avoid all these repeated threads. The Z06 is unique in very few ways to the Stingray when you get down to it.


https://www.corvetteforum.com/forums...-use-only.html

thebishman

Notice that Mobil 1 15W-50 is not included on that list? Interesting. Also, I don't remember seeing any oil listed with a greater than 30 weight.

xp800

The heavier weights wouldn't pass the fuel economy requirements of the spec and possibly others. The 15w-50 is track use only as well as higher phosphorous content than catalytic converters want for extended use.

JoesC5

Neither is the Mobil1 0-40 which is spec'ed for Corvettes going to Europe. I don't believe that Mobil1 5w30 is available in Europe, but not 100% sure.

glass slipper

I'm living in Spain for a few years, I'll check at the local auto parts store today but I don't recall seeing any 5W30 Mobil 1 either...I can get it all day long on the base at the Autoport store. There is plenty of 0W40 out in town and I'm pretty sure they have 5W30 since they're migrating to the lower viscosity oils here too, but I'm not sure if Mobil 1 is marketing that viscosity here.

ChucksZ06

From my research part of the Dexos spec is that the oil has to be lightwt ie 5 w 30. That is why only that wt mobil 1 is Dexos approved. You can bet fuel mileage is a big part of the Dexos spec.

JoesC5

I agree with you, but GM spec'ing 0-40 for the Corvette in Europe tells me that the heavier 0-40 oil isn't going to hurt the engine when hot or the 0w hurt it at a cold startup.

Plenty of C6 Z owners in the USA have switched over to 0w40, as I have. I don't believe that 0w40 met GM's old GM4718M spec for the C5's and C6's.

High Performance Engine Oil Specifications
GM4718M Registered Products
Revision Date: 1-June-2009
Product Name SAE Viscosity Grades
76 Super Synthetic Motor Oil 5W-30, 10W-30
AC Delco Full Synthetic 5W-30
Castrol Edge 5W-30, 10W-30
Castrol SLX Professional 4718 5W-30
Chevron Supreme Synthetic 5W-30, 10W-30
Coastal High Performance Full Synthetic 5W-30
Kendall GT-1 Ultimate Synthetic Motor Oil 5W-30, 10W-30
Mobil 1
0W-20, 0W-30, 5W-30,
10W-30
Northland, Synergy Synthetic 5W-30
Pennzoil Platinum Full Synthetic 5W-30, 10W-30
Pinnacle National Synthetic 5W-30
Q HorsePower 5W-30, 10W-30
Service Pro Full Synthetic 5W-30
Texaco Havoline Synthetic 5W-30, 10W-30
Valvoline SynPower 5W-30, 10W-30
Warren Full Synthetic 5W-30,





Now I see where GM is spec'ing dexos1 for the USA but since dexos1 is not available in Europe, they say to use dexos2. But, is an off the shelf dexos2 the same as Mobil1 full synthetic that GM says to use in the USA? Does ExxonMobil make a Mobil1 5w30 oil that meets dexos2 requirements? I know they make a 0w40 dexos2 Mobil1 oil, but the only 5w30 dexos2 oils made by ExxonMobil are not Mobil1, but conventional oils. http://centerforqa.com/gm/dexos2-brands