anders1118

I'm sure that has been discussed a lot. I did some searches and found only one thread which was not clear.

Ok so i go in for my 500 mile oil change at les stanford Chevrolet. Guy at the counter proceeds to tell me, that the 500 oil change is only for the Z51/Z06. So i tell him from what i have heard its all the vettes. He then contact a manager and asks, manager tells him its up to me, i can get it free if i like and it won't take away from my 4 free oil changes that i have left. OK so thats done.

While he's entering my info in the computer, i ask to confirm that they are using mobil one. He tells me that GM has not used mobil one for vettes since 2011. He says they use DEXO (synthetic). At this point i'm confused because all i have heard from this forum is mobil one. At this point i just tell him to use the dexo. I did some research while waiting on my car. Found one good forum dating jan 2015. It wasn't clear. Some guy named Fitchner (sp) said they must use mobile one. Went through half of the thread with no clear answer.

When my car was done i asked how much more it would be if i wanted mobil one in the future. He said its around $25-30 more. Not sure what to think at this point. I have 4 free oil changes left. Might just start paying $25 more for mobile one. How can this kind of stuff be so confusing for dealers. Specially a big corvette dealer that calls themselves the king of corvettes.

05c6vert

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

Glen e

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

I realize the above thread is pretty voluminous, but a few things ring true:

1. base cars do not get a fifth oil change, or a change of 500 miles.it's only the dry sump systems of the Z51 or z06.

2. Any C7 gets (4) Mobil 1 changes within two years. You choose when you want, not based on the percentage or anything else.

3. none of the above should cost you a dime.

But as I say many times, Just find a dealer that Will do all three above rather than trying to convince an idiot dealer. There are lots that do the right thing. I found at least two , interviewing around town here.

thrilled

It seems like the average dealer don't want to do Mobil 1. And they also don't want to change it early.I'm sure they get the bulletins.I believe they like to play dumb.

LIE2ME

Isn't DEXO (full synthetic) the GM version of Mobile 1?

LT1 Z51

DEXOS is the GM trade name for Synthetic Oil. Dealers who use GM DEXOS are in fact using Mobil 1. But in reality ANY DEXOS oil will do.

See: http://www.gmdexos.com/index.aspx

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

mikez06

We would not have started this whole conversation (ad nauseum) if the dexos used at the dealerships was FULL synthetic. I could care less what BRAND it is, as long as it's FULL synthetic.
And it's MOBIL 1. Mobile 1 is cellular.

LT1 Z51

Simple, dealers only know what OEMs tell them. GM rebrands many parts as "ACDelco" including Mobil 1 (which is what "ACDelco Full Synthetic" is).

What makes matters worse is that customers don't know anything either. Dexos is a trade name, not a brand. It defines that a full synthetic oil meets GM standards.

The same thing happens at Ford where people think Motorcraft is a brand, or at FCA where they use MOPAR. All those "service brands" are just rebranded supplier\aftermarket parts (sometimes with no changes, sometimes with minor changes).

LT1 Z51

To my knowledge it can't be. Even if some people on the list are called blended synthetic, my understanding is that they still are 100% synthetic. However over 80% of the ones listed have Full Synthetic in the name!

•dexos1® is designed for use with gasoline engines and replaces GM-LL-A-025, GM6094M and GM4718M.

GM4718M specifies a full synthetic. For dexos to supercede this specification it must at minimum meet the same requirement.

Unless someone at GM is a poor requirements engineer (which is possible) then this argument should hold.

anders1118

This is the thread i was reading on my phone while waiting for my car. Its a whole lot of back and forth. I see now that is says on Z51/Z06 but i was under the impression is was all corvettes. My salesman even told me to come back for an oil change between 500-1000 miles and he obviously knew my car wasn't a Z51. Thats what confused me.

I read that Dexo is a blend not full synthetic. I even read that mobil 1 is not full synthetic. Who know lol

So most of you got free mobil 1 oil changes?? For my next 4 oil changes i'm just going to pay an up charge of $25-30. Not even worth the hassle of worrying about getting reimbursed.

Thanks for the input guys!

Crossed Flags Fan

Tell your dealer to look in GM Global Connect: Ref. number: Service / Service Operations / G_0000208346 . The notification is there under the number above. Published 1/13/15.
And Z51 / Z07s get a free 500 mile Mobil 1 change in addition to the other 4 free changes.

AND an oil marked DEXOS compliant does NOT mean it is full synthetic.
Dexos compliant (meaning the oil company has paid a royalty to GM to use Dexos on its product) can also be a synthetic/petroleum blend

JerryU

Since it’s one of my favorite subjects I’ll provide my $0.02!
First GM only specifies the 500 mile oil change for dry sump cars, i.e.Z51, Z06. Thought they were the only C7's to get 5 not 4 free oil changes!
IMO here is why! A dry sump engine has an oil scavenge pump that drains all oil from the pan and sends it over to a separate tank. To get all the oil out you have to suck a lot of air with it! That air oil mixture goes into the dry sump tank and the air has to be what is called “burped” out! It comes out thru a hose from the top to a point just after the air cleaner in the air intake duct. Apparently the silicon that comes out of brand new engine seals and sealants depletes the “antifoaming agents” in the oil. Then foam forms from the air/oil being pumped thru the scavenge pump and some comes out with the “burped” air and enters the air intake behind the filter and causes oil to soak the filter and air duct. No scavange pump in a non-dry sump engine, no air being pumped with oil and therefore no excess foaming!
Since some eye’s roll with more than 2 lines of a technical response I’ll leave another post for the Mobil1!!

JerryU

Agree: GM has a spec for oil its called dexos 1 for gasoline powered cars. They will test your oil and if it meets their spec (and you pay them) you can put “meets dexos 1” on the container. GM doesn’t make oil and I believe most dealers buy 55 gallon drums of whatever they want that meets dexos 1. That is what goes thru a pipe/hose to the gun that puts it in your car. Since most GM cars don't use Mobil 1 that is not what is being pumped from the 55 gallon drum!
That can be what is called “full synthetic" or a blend of what is called full synthetic and petroleum based oil. However since about 2000 all the oil companies switched to “more refined” petroleum oil to make what they can now call "full synthetic oil!"
Very good article that explains when Mobil tried to stop Castrol from doing just that -- calling it "false advertising in their complaint!" However when they lost their case they switched to more highly refined, what some call "dino oil" as well since it cost about half of what the old oil cost, what I call truly “synthetic oil" made from mostly synthesized man made molecules. Here is a link to that article. Very well written. It was in Car and Driver Mag and the author equates this change to the Clinton, statement about his tryst with Monica! This is the first line: “Now that the meaning of "is" has gotten so slippery you need to grab it with both hands, we'd better keep an eye on longer words, too. One's already gone squirmy on us -- "synthetic," as in synthetic motor oil.”
http://www.caranddriver.com/columns/...mantics-column
PS: For the record I have been using Mobil 1 since it was introduced in ~1974 where it solved a problem with my 260Z and high performance Corvair! I still use it and buy it in 5 quart jugs at Walmart for ~$26. In fact did an oil change last week for my Z51 C7 and with the Mobil rebate I paid under $3/quart! It’s not the same as what I bought for the 1st 25 years but it’s also half the price!! About the same as other quality oils. I will use it until something else comes along that is “proven” to be better. However if you're using a dealer-I don't- might as well get it from the dealer free if you can. It’s probably better than as my friend calls generic no named brands, “Oh So Peachy Oil!” Google the 100+ brands GM lists as dexos approved. Some have names just like that!

donsar

The label on Dexos1 containers says "full synthetic". Strangely enough the DEXOS trademarks are owned by OnStar LLC according to the U.S. Patent and Trademark office records !!!

Calif Vetteman

Like JerryU, I have been using Mobil one, in all my cars, since it was introduced to the public in the early 70's, and it was a lot more expensive back then.

Regarding being charged extra. On my 500 mile oil change, at the dealer I purchased my C7 Z51 from, I was charged $46.00 extra for the Mobil 1.

I did contact Chevrolet Customer Service and after sending them my Vin.# and documentation that I was charged extra for requesting M1, I received a check in the mail for the $46.00 and and a letter of apology for being over charged.

JerryU

Nice to see GM came through and also to find another old timer that was an early adopter of Mobil 1! The use in my 260Z was somewhat unusual. That was the first year for Datsun to install an air pump in the exhaust and put hot water in the twin Hitachi SU’s. When the car warmed up, when accelerating it would surge and stop a number of times. The Datsun district manager looked at the car and said, we call it “Porpoising.” He said it’s not official but try this oil that Mobil is selling to the military in Alaska, Mobil 1 in the SU dashpots! It was hard to find and expensive but worked! Finally put on headers, richened the mixture and plugged the water hoses going to the manifold. After reading the specs put it in my Corvair where the oil ran hot. It would form a scum around the oil intake pipe. I had added an aluminum pan with tapered pins that went into the crankcase to help but the oil temp gauge I added still showed over 300 F as I recall. Mobil 1 solved that problem as well.
I had not seen that Car and Driver article until recently! Probably why I feel it was something that was slipped through with very little publicity for even a "gearhead" like me!

z28lt1

Do you have any reference that ACDelco Oil is a rebrand of Mobil 1? This would be the first I've seen of it, and odd, that they would factory fill with ACDelco Dexos and recommend switching to Mobil 1 for racing in certain cars if in fact they were the same. Also odd that they would need to direct dealers to use Mobil 1 instead of the GM oil the Corvette, if in fact they were the same. I know that ACDelco will often be a rebrand of something....just didn't know it was Mobil 1 in this case.

A replacement specification does not necessarily equate to exceeding the previous requirements. Better oil technology, and better technology to measure results mean they can evolve the requirements. For a hypothetical, in high performance applications is was probably easy to say that in order to meet high temperature running, they needed a full synthetic. But a better ability to not break down by some of the bends (those meeting Dexos), means they no longer require a full synthetic, but just an oil that doesn't break down at say 270 degrees, however the manufacturer wants to achieve that.

Again, as noted, Dexos is a specification, not an oil, and many will be full synthetic. But if we are referring to ACDelco Dexos oil -the one that GM dealers will use (and without double checking the part number GM likely calls for on non Corvettes), it does not say full synthetic.

LT1 Z51

My understanding (and this may be out of date as supplier contracts for ACDelco do change) is that at one time the ACDelco "Synthetic Blend" was Mobil 1 oil that didn't meet ExxonMobil's more stringent specification, but did meet GM's specification. Is it really Mobil 1? To me yes, to some maybe not.

JoesC5

Just about any blended oil will meet the dexos requirement(just look at the list of approved dexos oils http://www.centerforqa.com/gm/dexos1-brands ). Other oil companies have oils(both full synthetic and blended oils that meet dexos specs), so saying a dexos blended oil is a Mobil1 oil that didn't meet the full synthetic specs is not true.

Mobil1 is not a blended oil, but is considered a full synthetic, and it meets the dexos specs.

Think of a blended dexos oil as a RN(ie:synthetic blended oil) who can perform some medical procedures but not all the procedures that a MD can. Think of full synthetic such as Mobil1 as a MD(ie:full synthetic oil) that can perform all medical procedures including any that a nurse can do.

A RN can't do all that a MD can, but a MD can do all that a RN can do.