[Dutch1LE]

2019 zl1 1le. Before I go a head and order my oil.. I just want to confirm this is correct.
This oil for street driving.
https://www.amazon.com/Mobil1-123875...ps%2C96&sr=8-4

And this oil for the track?
https://www.amazon.com/Mobil-Advance.../dp/B07GL2XDTG

I don’t see anything about this oil being dexos 2 approved etc.


Or would I be ok with this 5w-50 supercar to cover me for both street and track? So I don’t have to switch between the two.
https://www.amazon.com/Mobil-5W-50-S.../dp/B0BWPLYYTT

Also what oil filters do you run? ACDelco, mobile 1?

Thanks for your input.

[Msquared]

Your first two links are correct based on the the specs in the manual. The 15w50 is not Dexos certified, and that is one of two reasons you shouldn't use it for regular street duty.

The Supercar 5w50 is new to me. However, based on its spec sheet from Mobil, something doesn't seem right. The viscosity at 40C (104F) is 112mm2/s, whereas the 0w40 Supercar is only 69. That seems really high for a 5w oil. For example, their 5w40 FS has a 40C viscosity of 81 and for the 15w50 it's 125: barely higher than the 5w50 Supercar. I realize the winter grade is measured at much colder than 40C. I'm just surprised at how thick the 5w50 is when it's that much cooler than operating temp. But the point is when you cold-start your car on a hot summer day, it will take nearly twice as long for the oil to flow to everything with the 5w50 in there. For some maddening reason, Mobil 1 isn't publishing the high-temp/high-shear viscosity of the 5w50, so we can't directly compare. However, with a 100C viscosity of 18.1 vs the 0w40's 12.9, we can infer that the HTHS numbers are better for the 5w50. I would hesitate to use this stuff as a full-time oil unless/until GM updates its recommendations.

[wakespeak]

15w-50 for track use. A lot of us use it on the street too in the warmer months, although you're ok down to 25F. I reviewed a Corvette LT4's used oil analysis for this kind of mixed use and it looked good. Mobil1 15w-50 is now in API SP rated form, a little thicker than it was and better for direct injection like we have.

Might be why GM came out with 5w-50 DexosR for both street and track. DexosR replaces Dexos2 for the Camaro, Corvette, or V-Series Cadillacs. The zinc levels are about same if I remember, about 1300 ppm, as 15w-50. Zinc helps when the oil film gets stretched thin to act as a barrier but the downside is it can shorten catalytic converter life as some of the oil get burned normally. Having said that I used high zinc oils in other vehicles into the 170k miles and they still pass emissions.

Oil filter UPF64 has greater strength but also a higher bypass rating. This is useful if you use 15w-50 on cold mornings and rev the engine before the oil is warmed enough. With the higher bypass rating the filter doesn't bypass and send the oil back into the pan. Wix 10290XP otherwise is great.

DexosR FAQ

[Dutch1LE]

I am going to grab the upf64 filter for sure. See the more I read the more confused I get.. like you stated some ppl run the 15-50 on the street as well, but it’s not dexos rated? I live in upstate NY and we do get some cooler weather. So that thicker weight oil concerns me leaving it in. I don’t have cats so I’m not worried about that. I would really like to limit the oil changes and not have to switch back and forth. Not trying to be controversial, but isn’t the 5-50 the same thickness at warm temp as the 15-50? So technically shouldn’t it have the same coverage as far as high g stuff goes? But the 5 vs 15 is better for cold start and colder weather correct? So isn’t this the best of both worlds? Also the 5-50 is dexos r. To me the do it all seems to be the new 5-50 unless I’m not understanding oil completely lol.

[Msquared]

Originally Posted by Dutch1LE

I am going to grab the upf64 filter for sure. See the more I read the more confused I get.. like you stated some ppl run the 15-50 on the street as well, but it’s not dexos rated? I live in upstate NY and we do get some cooler weather. So that thicker weight oil concerns me leaving it in. I don’t have cats so I’m not worried about that. I would really like to limit the oil changes and not have to switch back and forth. Not trying to be controversial, but isn’t the 5-50 the same thickness at warm temp as the 15-50? So technically shouldn’t it have the same coverage as far as high g stuff goes? But the 5 vs 15 is better for cold start and colder weather correct? So isn’t this the best of both worlds? Also the 5-50 is dexos r. To me the do it all seems to be the new 5-50 unless I’m not understanding oil completely lol.

The 15w50 is not Dexos rated, that's true. Not having cats, that makes that less important but I think it still matter with respect to valve deposits. The 15w50 and 5w50 are almost identical in kinematic viscosity at 100C. What we don't know about the 5w50 is its viscosity under high-temp/high-shear conditions. Mobil isn't telling us. That's a key to assessing how well an oil will do on track. With its wider range of cold and hot viscosities, its HTHS performance is likely a little worse than the 15w50's excellent 4.5mPa.s. But it may still be really good.

The cold start flow of both 50w oils on a summer day is still a good bit worse than that for the 0w40. This is the kind of oil you would want to let warm up for a minute before driving anywhere, especially in cooler temps.