My lovely wife just got back from having the oil changed in our new 2017 Z51 @ 498 miles. She asked the tech "Did you put in Mobil One"? His response was "No , it's not necessary, we use Dextros on all the Corvettes, never had a problem". Now I went to public schools but I can read, it pretty clearly states (in bold print) "Use Only Mobil One" in the manual. On top of this, this is the same dealership that just did my GS, probably didn't use the correct oil in it either. So, do I let it slide, inform them of there mistake, or raise hell? Kinda sounds like a setup to deny future warranties if the engines blows up? Your opinions would be helpful.

 

I wouldn’t be to worried, nor be concerned about the warranty, but would let them know what you expect the next time. And remind them again when you take your C7’s back for the next change.

 

Pretty interesting read about why GM dealers use it: http://www.agcoauto.com/content/news/p2_articleid/178

 

In reality you have nothing to be worried about.

But if you have the time on your hands to go back to the dealer, and feel ripped off, then you could have them replace it on principle.

 

Hey Lonegun, nice having 2 C7s!!

No worries about your warranty. For warranty, just need to use Dexos licensed oil, and they did (Mobil 1 is also a Dexos licensed oil).

However, frustrating? Yes. Lots of discussions on this. In fact, your GS likely has a label installed around the filler cap that states they should use Mobil 1. As you state, the owners manual also stipulates Mobil 1. IMO, a good oil that is Dexos 'approved' will be just fine. But if it were me, I'd gather up the information that you can - copies of the owners manual, the label on your GS, service bulletins, etc., and take them back to the service manager and calmly point out that, irrespective of what the tech told your wife, they are not in keeping with the directions from Chevrolet and you expect them to live up to the directions from the manufacturer.

I'm really disappointed when I hear of experiences like yours. I'm blessed to have 2 dealers that take care of our Z51 and now our GS - one Caddy and one Chevy - both outstanding experiences every time I go to one of them. And we purchased both C7s from the east coast (Kerbeck and MacMulkin).

My recommendation is to gather the information, take the copies into the service manager (make an appt to see him/her), and calmly discuss the situation. I'll bet you get a good outcome. If you go in 'hot', the defensive hackles are up and communication will likely go south. A good opener is 'I need your help.............'.

Good luck - let us know what you do.

 

I'd not be worried about it because frankly the tech is correct and honest. If he would have said yes we did how would you know anyway? I wonder how many owners are humored by their dealer and think they got mobil 1 and get whatever?

Thus I do mine myself and hope the discounted Mobil 1 at WalMart is the real deal!

 

There is no need to be worried. The only harm in this is you didn't get what GM reimburses the dealership to use but there is nothing wrong with using the proper grade of good oil and since the dealer used the required Dexos licensed variety there is zero warranty concern.

But given the service was less than spectacular since the service tech didn't follow protocol:

1. double check that the correct amount of oil is in place. Remember you have a dry sump so the oil needs to be checked a few minutes after the warm engine is shut off. If you wait too long the oil begins to slowly drain back into the sump and you will get an false low reading.

2. For future service consider another dealer because this one was careless with an easy task which wouldn't give me a lot of faith that the service department will faithfully follow procedure for more involved service issues.

 

I disagree with point #2....... at least this dealer was honest!!!

 

Very easy to know. The service order will specify the GM Part Number that was used. It will either be the part number for Mobil 1 or for their bulk generic Dexos licensed oil.

 

I had the same discussion with the Caddy dealer when I took my new CTS in for it's first oil change (on GM maintenance) who stated that "Dexos is a synthetic blend oil". They wanted to charge me for M1 so I just left and did it at home (I have a lift in my garage). Whatever one they use, it's on them for future issues.

 

To the OP, considering my experience (any many others) with dry sump oil changes @ the dealer, have you checked the oil level after the changes yourself, using the proper procedure for checking the oil level on the dry sump system?

If they can't be bothered to put the right oil in, you have to wonder if they followed the correct procedures to fill to proper level. Many of us have had our cars overfilled at the dealer and had to have it corrected. Myself, I gave the local dealer one shot on my first "free" change, but will be going back to doing my own at the next change.

 

Both Dealers that I've used for oil changes confirmed Mobil 1 is to be used. They mentioned something about "Y" something cars where it's required (or recommended). BUT that was only AFTER I TOLD THEM TO ONLY USE MOBIL 1. If you don't say anything before they do the work, I'm sure the service will use the cheapest option.

I suspect the guys comment about it not being needed is more of a cover his A response. Notice he didn't say it not in fact recommended (i.e., he was supposed to put in Mobil 1). He's just giving his opinion and not GM policy. So, in your case, you can go back and request they put in the recommended oil (another oil change) or, if you don't trust them and can't 'suffer fools' you can find a lift and do the oil change yourself. it's really no different than any other car excepting for the z51 specific procedural elements.

 

Nothing to worry about, they were honest with you and really no big deal. Your engine will not know the difference.

 

Dealer used Dexos in my car as well as part of the free 2 year maintenance program. Oh well.

 

It's not going to harm the car at all just I am a diva and refuse to use anything other than full synthetic in my car.

 

Happen to know if "B88865639 Oil" is the Mobil 1 or the Bulk stuff??

 

I just couldn't decide between the GS and Z51, plus they're practically givin em away, what the heck, right?

 

All true about the worry, but there's more to it. Since GM has directed that M1 be used in C7 Corvettes (ref. PIP5290E) and you are given 2-3 "free" oil and filter changes with the purchase of a new C7, you have essentially already paid for them. This "free" stuff isn't really free. If you don't choose to take advantage of it and insist that the dealer do the right thing you've wasted what they've already charged you for the oil, filter, and labor.

To the OP, I would contact Customer Support and send them the invoice showing the incorrect part number used for your oil change. Based on previous discussions here they should take the side of the customer, contact the dealer, and make it right. The correct part number for M1 by the quart is 12345885 and I would insist that this show on the invoice next time.

On the positive side, over a year ago the Dexos blend was reportedly phased out in favor of a full-syn version, likely made by Exxon-Mobil but also likely not M1. It's probably Mobil Super Synthetic, a cheaper full-syn oil with specs falling short of M1. That said, it won't hurt anything except possibly your pride for being ripped off.

 

I purchased a Mobil 1 oil filler cap (Amazon) to replace my stock Dexos one. Not a sure thing but hope it helps along with informing dealers GM specifies M1 (and taking a copy of the directive to the dealer in case I need to use it).

 

I had the 500 mi oil change done on my '18 Z51 back in August and the service order says Mobil 1, but the oil part number showing is 89021624 (08800-BOPCKT) I did a brief search on that part number and found this: 89021624 - OIL,ENG 5W30 SYN MOBIL 1-OPT 2, STD

More than one part number, bulk Mobil 1, or? Curious minds want to know...

Btw, I got a slick Mobil 1 brochure with the car's documents, FWIW.