Is GM’s Dexos 2 requirement for the LT4 on the C7 Z06 and CTS-V strictly emissions based?

[Neversatisfied02]

OK, the FS 0W-40 is not the ESP/Supercar 0W-40, it's the Euro 0W-40, which is the same additive approach as the HPL Super Car 0W-40; it has a full-SAPS additive package.

You’re right. I messaged him to clarify that when I noticed he mentioned 0w40 FS and that it wasn’t a lower SAPS oil… which the ESP/Supercar is to my knowledge. He was in fact referring to the Euro 0w40 FS with what he said. I’m glad I asked him about that to clarify.

 

[Neversatisfied02]

How are the oil temps and PSI?

Mobil1 Euro 0w40 has been an excellent oil for many years. Didn't care or need ESP/Supercar, or whatever the current marketing terminology is, or any other emissions saving oil. Give me an engine saving oil. I can change out a catalytic or o2 sensor a lot quicker and cheaper than pulling an engine for a complete rebuild. That Rotella T6 5w40 is a good option too.

Mobil1, as do other like Castrol/Valvoline/Pennzoil, Amsoil, Redline, HPL, Torco, MPT,.... all have plenty of products to choose from in the 40 and 50 grades.

Weather permitting, I don't see the need for 0w-anything, and 5w40 10w40 are also options, as is the previously mentioned 5w50 and 15w50. If it were mine, I'd start with M1 FS 15w50, and gather UOA data to see how it does.

Full synthetic motor oil | Mobil™ Motor Oils

Full synthetic motor oil outperforms conventional motor oils and enhances the protection and performance of your vehicle.

www.mobil.com

My oil temps are good. At operating temp, I see 30-31 at warm idle and temps of approx 180*. Car has a 160* stat in it so it stays a little cooler. If I’m hard on it back to back, I might see 200*ish on the oil temp but that’s about it.

I agree on the emissions focused oil. That’s the exact reason for my skepticism. That’s exactly why I started thinking maybe the 5w40 Rotella T6 might be a better option as well as being much easier to source. I will say tho, Dave said the diesel oils aren’t as good as they once were so it leads me to believe he wouldn’t recommend it. He seemed to like his oil or that euro mobil 1 0w40 FS. That said, I’m with you on the 0 weight. I mean the ideology of a quick flowing oil at startup is great but it just seems like a 5w or 10w would be a little safer to take the abuse. Of course this is just gut feeling with no scientific proof. Lol

The 15w50 being recommended for track use had my attention as well. I don’t track the car but it sees a good bit of spirited driving with the odd longer distance drive. I wonder if that would be a good full time option? Only thing I could see with that is the fact I’d want to be sure to let it warm up until oil temps are 160* or better before running it hard.

 

[Greasymechtech]

I would say that the 15w50 would be a good full time option.
But, your oil temps are under control and you could save some power with the 0w40's or 5w40's. Thick oil costs power to pump and swim in.

UOA will help. Run the 0w40 a couple times, the TDT/Delvac/T6 5w40 a couple times, and the 15w50's... and see if any scream mercy.

POLARIS Laboratories

POLARIS Laboratories

polarislabs.com

 

[Neversatisfied02]

I would say that the 15w50 would be a good full time option.
But, your oil temps are under control and you could save some power with the 0w40's or 5w40's. Thick oil costs power to pump and swim in.

UOA will help. Run the 0w40 a couple times, the TDT/Delvac/T6 5w40 a couple times, and the 15w50's... and see if any scream mercy.

POLARIS Laboratories

POLARIS Laboratories

polarislabs.com

Yeah, I imagine the 15w50 would be just fine. It’s also easy to source which is nice.

My oil temps only climb a bit as expected when I’m making pulls with it but then come back down to normal once I’m just cruising again. And you’re right. I’d hate to give up any HP unnecessarily but I’d be ok with it if it means better protection/ reliability. I was hoping he’d have better to say about the T6. I’ve got a stack of it in the garage from when it was getting tough to find and I stocked up with a couple boxes of it for my truck. That’s why I was leaning toward trying it in the V. I’ve run it in several vehicles over the years with good luck but wasn’t aware of anything changing with their formula.

 

[userfriendly]

The 0w40 Delvac has a higher HTHS than any of the 5W40s mentioned so far @ 4.1
Sources say that Delo 400 XSP 5w40 CK-4/SN+ has an HTHS of 4.2

Edit ''' Might as well mention Ravenol Turbo 5w40. I think they are tied in with Evonik chemical in Germany.

 

[Neversatisfied02]

The 0w40 Delvac has a higher HTHS than any of the 5W40s mentioned so far @ 4.1
Sources say that Delo 400 XSP 5w40 CK-4/SN+ has an HTHS of 4.2

Edit ''' Might as well mention Ravenol Turbo 5w40. I think they are tied in with Evonik chemical in Germany.

Nice! I’ll have to do some searching for those to see if I can find them. I’m sure they’d both work well. I wonder at what point/value is HTHS enough? At short intervals and without reach crazy high temps, an oil with a HTHS of 3.5 might be just fine. Of course having better never hurts.

 

[userfriendly]

Nice! I’ll have to do some searching for those to see if I can find them. I’m sure they’d both work well. I wonder at what point/value is HTHS enough? At short intervals and without reach crazy high temps, an oil with a HTHS of 3.5 might be just fine. Of course having better never hurts.

IMO, it's better to have it and not need, than need it and not have it. The oil can be too thick all of the time, but too thin only once.
Qualifing oils tend to be on the ragged edge of being too thin and could cost an engine in trade for the pole position.
In bracket racing, repeatability wins the trophy. In road racing, if you don't finish you can't win.
If you're not first, you're last.

What do you think of BITOG so far?

 

[Neversatisfied02]

IMO, it's better to have it and not need, than need it and not have it. The oil can be too thick all of the time, but too thin only once.
Qualifing oils tend to be on the ragged edge of being too thin and could cost an engine in trade for the pole position.
In bracket racing, repeatability wins the trophy. In road racing, if you don't finish you can't win.
If you're not first, you're last.

What do you think of BITOG so far?

Solid point. I’ve always run Valvoline VR1 20w50 on my built motor cars. Of course tolerances are different so that’s ok. I’d imagine that would be a little much for a SBE LT4. Who knows though? 15w50 isn’t far off and that’s recommended for track use.

Man, y’all have been great to chat with! I can’t tell you how many times I googled a question and I’d end up getting sucked into some of the threads on this site. Lots of good/interesting info! Glad I joined! Now I can bother folks with my own questions and indecisiveness… 😂