Thoughts on oil type/weight for 5BW?

[MZucarelli]

I noticed the new C8 grand sport with the 6.7L LS6 takes 10qts of 5w50 supercar mobil 1. Same as the C8 Z06 i believe. Thats a change from the 7.5qts of 0w40 supercar mobil1 in the base car.

With GMs other oil related issues with their trucks, this doesnt surprise me that we're going to oils that don't feel like water.

Anyone considering running the thicker oil in their 5BW LT4?

My wife drives a diesel suburban and I sure as heck dont put the 0w20 they call for in the LZ0. Just got my 5BW a few months ago and im a little more cautious with this one and wanted to get some opinions. Thanks!

I suspect this will be a polarizing topic. Interested to see the comments.....

 

[Melon]

In the supplemental manual that came with the ZL1, GM recommended 15w50 for track driving, but also stated it was to be drained and refilled with 0w40 before normal driving.

5w50 is pretty thick for street use, but I'm sure it's to handle street and track driving in the C8.

0w20 oils are to meet emissions targets. GM's issues with those recently was more from a manufacturing error point than a lubrication issue. If the vehicle never sees heavy use and can keep the oil in the ideal temp range, 0w20 is fine.

 

[RDATLTE]

In the supplemental manual that came with the ZL1, GM recommended 15w50 for track driving, but also stated it was to be drained and refilled with 0w40 before normal driving.

5w50 is pretty thick for street use, but I'm sure it's to handle street and track driving in the C8.

0w20 oils are to meet emissions targets. GM's issues with those recently was more from a manufacturing error point than a lubrication issue. If the vehicle never sees heavy use and can keep the oil in the ideal temp range, 0w20 is fine.

I believe that the 15W-50 for track use was only recommended for the ZL1 1LE.

 

[Melon]

It's the same engine.

I'd have to go back and check you might be right. My main point is they only stated it to be used on the track, for street use: 0w40.

 

[RDATLTE]

It's the same engine.

I'd have to go back and check you might be right. My main point is they only stated it to be used on the track, for street use: 0w40.

Correct on both counts. I believe it's the increased G Forces from the wheel & tire and suspension differences between the 2 models that calls for the oil change for track use only.

 

[Melon]

Sweet, thanks for the clarification.

 

[MZucarelli]

Im definitely not tracking my car. Just found it interesting the standard oil for the LS6 is not 0w anymore. None of these cars are economy cars. Seems shortsighted of a manufacturer to sacrifice wear, to gain mpg. The counter argument ive heard to running thick oils, is that machining tolerances are better now. I just still have a though time buying it.

 

[Melon]

They have to make these cars suitable for Minnesota winters and Nevada summers. That's a huge range of ambient temps.

I'm sure you can go up or down based on your own local climate, driving style, etc. Without causing any major issues.

 

[MZucarelli]

They have to make these cars suitable for Minnesota winters and Nevada summers. That's a huge range of ambient temps.

I'm sure you can go up or down based on your own local climate, driving style, etc. Without causing any major issues.

I think we hit 90 as a low last week here in Phoenix, AZ. LOL

I've had fun playing with the LZ0 diesel. Theres alot more of them, and alot more support on forums due to the sheer # of units out there. Including some pretty dedicated enthusiasts that lab test their oils after trying different viscosities. 5w30 seems to be the sweet spot for that particular engine.

 

[vagabond]

Something to think about is low viscosity helps w/ cold startup oil dispersion. So not just EPA/CARB. IIRC there are very minor differences between the Camaro LT4, CT5BW LT4 (clean side catch can, supercharger lid), and Escalade LT4 (accy drive, supercharger). Probably not enough to make a difference re: oil recommendations.

If I tracked the CT5BW every other week and/or lived in Phoenix and garaged it I might think about 5W. But for now I daily drive my car in all PNW weather and use 0W-40 supercar (OEM recommendation).

Either way change the oil frequently and life's good. The owner's manual recommends 7.5k intervals but I shoot for 5k. The engine oil life system seems to do a good job of knowing when I track the car. I tracked it a lot last year but not as much this year.

 

[KatyTxCT5V]

Funny subject for LT4’s.
My 2016 Z06 came with M1 5w-30 & my 2017 ZL1 came with M1 5w-30.
I sold my ZL1 in 2019; but kept my 16 Z06 until recent.

I switched the Z06 to M1 0w-40 Supercar because my 22 5BW came with M1 0w-40 SC and was easier to keep all the same oil.

I switched my 22 GMC AT4 with 6.2 to M1 0w-40 SC because all the BS with 0w-20. I traded it in Jan. My new 26 BWM runs 0w-12, for now, lol.

I still and will continue to run M1 0w-40 SC as long as they make it. I’m in Houston area and last week was high 90’s and expect some 100’s soon. All my cars sleep in a 75F climate controlled garage, which makes them and me happy.

 

[blkout]

0W-40 for daily driving. 5W-40 for a track car or warm year-round climates.

 

[RDATLTE]

Funny subject for LT4’s.
My 2016 Z06 came with M1 5w-30 & my 2017 ZL1 came with M1 5w-30.
I sold my ZL1 in 2019; but kept my 16 Z06 until recent.

I switched the Z06 to M1 0w-40 Supercar because my 22 5BW came with M1 0w-40 SC and was easier to keep all the same oil.

I switched my 22 GMC AT4 with 6.2 to M1 0w-40 SC because all the BS with 0w-20. I traded it in Jan. My new 26 BWM runs 0w-12, for now, lol.

I still and will continue to run M1 0w-40 SC as long as they make it. I’m in Houston area and last week was high 90’s and expect some 100’s soon. All my cars sleep in a 75F climate controlled garage, which makes them and me happy.

True story, my 2018 ZL1 1LE came with 5W-30 and then at some point shortly after they changed to 0W-40. I remember getting a new fill cap reflecting the new spec.

 

[Melon]

still and will continue to run M1 0w-40 SC as long as they make it. I’m in Houston area and last week was high 90’s and expect some 100’s soon. All my cars sleep in a 75F climate controlled garage, which makes them and me happy.

I'm in Baton Rouge. I've had enough of summer. This is brutal.

 

[blkout]

I'm in Baton Rouge. I've had enough of summer. This is brutal.

Same here in GA where the heat index is 100-105 every day.

 

[Motorin Mark]

Same here in GA where the heat index is 100-105 every day.

Here in Daytona too, and our humidity is also off the charts!

 

[Melon]

Cadillac Hotwings.

 

[Kawman]

After all the discussions on this topic why are people still dropping the first number from 5w to 0w?

Unless it's negative 20 degrees, it's absolutely the wrong thing to be doing. Going to a lower weight oil provides better lubrication at start up in EXTREMELY cold environments. I'll say that again, 0w oil is for extremely cold environments! You are not doing your engine any favors by using it in summer or hot environments. If anything you should be going to a 10w40.

 

[blkout]

After all the discussions on this topic why are people still dropping the first number from 5w to 0w?

Unless it's negative 20 degrees, it's absolutely the wrong thing to be doing. Going to a lower weight oil provides better lubrication at start up in EXTREMELY cold environments. I'll say that again, 0w oil is for extremely cold environments! You are not doing your engine any favors by using it in summer or hot environments. If anything you should be going to a 10w40.

The OEM oil is 0w, there's nothing wrong with using it unless you're tracking the car, at which point you might be best to switch to a 5w or 10w.

 

[Kawman]

Mr. Blkout, my comments are directed at the topic of discussion, not you, so please don't take offense.

For the 4BW, the OEM oil is 5w30 with a revised recommendation to use 5w40.

The 0w is for EXTREMELY cold environments, like -20 degree Minnesota winter mornings. The 0w number only relates to your cold start. The 0w number has nothing to do with tracking a car. For track use it's the second number you raise, not the first one, so you'd want a 5w50, or a 10w50 for the track if going further than the revised 5w40.

There is no reason, no benefit to using 0w40 versus 5w40 oil and there is actually a detriment. The wider the gap between the 2 numbers the faster your second number shears down to a lower protection level. 5w40 absolutely is better for the 5BW than 0w40, unless it's extremely cold.

Granted this thread was about the 5BW, not the 4BW, but the fundamental principles of oil remain the same.

GM gives the 0w40 recommendation knowing some cars live in Alaska and some live in Arizona. A car that lives in Arizona would be better off not using the 0w40. One last time, there is a very specific reason for the 0w number and that reason simply does not exist in Arizona or any other hot climate.