Patman

Now that there is a new Mobil 1 0w40 coming out that is dexos2 approved, I am wondering if this now opens the door for other dexos2 oils to be used while still under warranty? For example, Pennzoil makes a dexos2 5w30 called EuroL which is thicker than their dexos1 5w30s and has a higher HTHS (3.68) than even the new M1 0w40 ESP does (it's around 3.5) Up until this oil was introduced, I was under the impression that only dexos1 oils were allowed while under warranty, but dexos2 oils are always going to be slightly thicker oils with 3.5 or higher HTHS (which is definitely beneficial for harder driving applications)

The benefit of that Pennzoil Euro L oil in particular is that it's currently available at Walmart and is sold in 5 quart jugs, while the new M1 0w40 ESP is still months away from being sold in retail outlets, and there is no guarantee it'll even be sold in the 5 quart jugs at a reasonable price. My fear is that with such a low market for this new 0w40 (basically just C7 owners at this point) that it won't be priced competitively like Mobil 1 5w30 is.

I guess the main question is, can we now use any dexos2 oil and still maintain our powertrain warranty?

Jrw96

Gm does always recommend you use the correct wieght and dexon or better. Dexos is a semi synthetic, if you use a full synthetic or semi synthetic your gm powertrain warranty is still good. Just please save receipts of oil and filter changes if you do it you self. Gm will not warranty an engine if they cannot see proof that it was maintained properly.

Patman

dexos doesn't mean semi synthetic. dexos1 and dexos2 are different specifications and it can be either synthetic or semi synthetic (although I believe it's difficult for semi synthetics to acheive dexos2 certification)

What I'm getting at with this post, is that things have changed since the owner's manuals were printed for the 2014-2018 owners. Originally they called for 5w30 oil meeting dexos1. Now the latest recommendation is this new Mobil 1 0w40 ESP which meets dexos2. So because of this new recommendation, I now wonder if other dexos2 oils are allowed under the warranty, as long as they are either 5w30 or 0w40.

jvp

That's always been the case for any generation of Corvette. As long as the oil in question meets the recommended rating, it's allowed/covered. Manufacturers can't (legally) force you to purchase a specific brand of oil to maintain your warranty. They can require a rating, and suggest a brand. But that's it.

Really don't see the need to send this to Tadge.

Patman

But I do think it's something that needs to be confirmed by GM before people just assume it's ok. I would hate to switch to an oil that might void my warranty just because I'm guessing it's ok. It's such a grey area because the new recommendation isn't in the owner's manual of older cars, so we don't know if this new oil is the only dexos2 oil allowed, or if all dexos2 oils will now be allowed.

Bill Dearborn

Dexos2 is a specification that GM has announced as being applicable for all Corvette engines back through 2011. As long as oil meets Dexos2 specs it is good. No further explanation required.

Bill