manic mike

I recently got my 500 mile oil change done and I didn't do my homework before going into the dealership. I asked for Mobil 1 and the service manager said they use GM dexos, per GM, and that it was manufactured by Mobil.

After I got the oil change I did my homework and have read the 814 posts on the 41 pages of the Mobil 1 sticky thread and found out the service manager was wrong. Also, maybe a half dozen, or so, posts specifically compare the two. My impression is that Mobil 1 is superior but GM dexos is OK.

I am planning on keeping this car for a long time. If I was not I wouldn't bother with this thread. My question is should I change out the oil now with Mobil 1 or just wait until the next oil change is due?

BTW, I put about 8k miles per year on my C6 and I drive in a spirited and aggressive manner. Those miles were not long road trips and both cars are not my dd.

Thanks for your input!

millpond

You will be just fine to run the Dexos until your next oil change.

Steve_R

Dexos is a specification, not a type or brand. Mobil 1 meets the Dexos spec, so could be referred to as "Dexos oil" as well. You paid for Mobil 1 in the purchase price of the car, and the dealer gets reimbursed for Mobil 1. Because of that I'd take it back and make them do it right. I wouldn't worry about longevity of the engine at all with the semi-synthetic GM Dexos oil in it since that's what they require.

Kracka

Dexos1 that dealerships use is a semi-synthetic. It's good oil, my first change was done with it too instead of Mobil 1 before the debate was cleared up and its not a big deal. Many other 2014's were also in the same boat

dvilin

Red C8 of Jax

Do you have a C-6 or C-7?

wgood

No go to the sticky that talks about Mobil 1 use and give them a copy !!! Wayne

GOLD72

Mobil 1 is superior but you will be fine with dexos1 until next change.

nmvettec7

Totally agree with Wayne above.

The information found on the CF can be of great value. Print the Mobil 1 info here from the forum and take it to the dealer.

I just did this recently regarding my removable top. I printed the TSB for the roof creak issue.

I went to the local Chevy dealer and wanted to schedule an appointment on Jan 7th, 2016 to have the roof fixed. The service guy stated "there are no recalls on the removable roof". I stated the fix is not a recall by GM, but a TSB that was issued by GM. He immediately looked up the TSB number and reviewed the printout I provided from here on the CF and immediately stated "you are right". He ordered the 4 parts needed to retrofit the parts and scheduled my appointment for Jan 7th, 2016.

When going to the dealer, be sure to have any supporting info or documents to support the work you want to be completed.

GizmoZ

I just went through this myself recently. I asked the service manager to fill the car with Mobil 1 and even double checked with him before they performed the first oil change at 500 miles. They always bend over backwards to accommodate me and take extra care of the car so I assumed that was taken care of. I get the car back, drive home and start looking at the invoice. I didn't see any mention of Mobil 1 so I ran the P/N for the oil they added and sure enough, it was the Dexos blend. Not only that, but it was overfilled.

If the oil level was okay, I probably would have left well enough alone, but I was not comfortable or happy with the extra oil, so I went through the trouble of showing the service manager the documentation I found here on the forum about the Mobil 1 recommendation. His rationale for going with the Dexos over the Mobil 1 I requested was the oil cap saying Dexos rather than specifying Mobil 1. I can understand that and they were apologetic and more than willing to dump the Dexos and fill with the 9 quarts I requested and I took the tenth home and added about half to get the oil level where I wanted it.

I've since added a Mobil 1 cap and won't hesitate to use the dealer again now that we're all on the same page. The other thing that I was sort of hung up on was the factory fill with Mobil 1. I'm not sure if they are filled with Mobil 1 at the factory but that's what I've read and if that's the case, it doesn't seem right to go from full synthetic to a synthetic blend.

PLRX

Engine builders will tell you not to "break-in" a new engine with synthetic oils.

Once your free oil changes expire, buy Mobil 1 in Walmart (cheap), and all will be good.

rmorin1249

There are numerous other premium oils that are as good or better than Mobil 1. GM has a relationship with Mobil. That's the reason it's being used not because it's necessarily the best. Just MHO.

No worry about your dexos.

iclick

When I bought my C6 I was given one free oil change, and unlike today with the C7 Mobil 1 was not specified as the oil of choice by GM. I did some research and decided the additive package and overall quality of the GM blend was very good and used it for that first change, but then moved to Mobil 1 thereafter (DIY). I also decided that it was probably made by XON, although I didn't see any definitive evidence of its origin.

The blend has a decent level of moly in the additive package, which is important to me, and I feel that for street use it is fine a C7 as long as the change interval isn't too long. I wouldn't worry about it but would move to M1 for subsequent changes. If the dealer does it for you make sure he understands the M1 requirement in C7s and the M1 part number shows on the invoice.

HANNY

no worries. I would look for threads that say "i switched to mobile 1 and blew my engine up" I don't think you will find many ,,,, all is well

MikeyTX

I call B/S ............ The assembly plant at B G fills the engines with Mobil 1 full synthetic. I had this verified when I did my R8C delivery on the 14th of this month. That is such an old wife's tail that goes way back to when Moses carved the tablets.

Vetteman Jack

However, do whatever you feel comfortable with.

gve

The Mobil 1 Advanced synthetic 5W/30 has recently been updated by 540ratblog in this link.

https://540ratblog.wordpress.com/

It tested #4 with a 117,000 psi which is pretty good based on all the oils tested. You have to scroll down a ways to see where the results are, its interesting reading.

JerryU

For two items on my C6 I recall the Service person who did the scheduling, liked me bringing the Bulletin numbers. Then she would wright up the order so they got paid. The Bulletin would say, "If the customer complains about...." and she would put on the work sheet, "Customer complained about...." exactly as written. Got my C6 roof fixed as well a free differential oil change by bringing her the Bulletin numbers I found on the Forum!
Can't expect the Service folks to be on top of all these issues on the many cars they deal with. And as noted when not a recall, you have to "properly" complain about specific things!

GOLD72

BG has factory filled all corvettes with Mobil 1 since about 1993 until GM introduced the dexos1 spec for MY2011. Can't speak for model years 2011 and newer as to M1 vs dexos1.

GOLD72

Logistically for GM, it would make sense that all vettes would be factory filled with M1 but allow owners to use dexos1 for their wet sump engines.