[MR's 2SS]

Originally Posted by zxspeedspec

This is the only correct answer. Tadge himself answered in the C7 forums about how intelligent they designed the OLM and how it even tracks even RPM use and how much time it's spent at certain RPMs at what engine temps meaning it'll even decrease faster during a track day. No reason to second guess this monitor.

I will say you should check your dipstick. 10 quarts is generally half a quart too much since the last quart doesn't fully drain. It's probably not enough to cause head gasket issues, but depends on how aggressive you get with your driving.

When I change my oil and filter the 10 qts barely reaches almost but not quite to half of the crosshatch on the stick.
I have added an additional fraction of a quart to bring it solidly to half after running it and re checking.
I know the dip sticks can be different and the tube could be set differently into the block.
Either way I cant see 1/2 quart either way making a difference.
Only 3500 miles and I havnt consumed any oil at all.
I thought it might use a bit during break in.

[hamp]

I own a 2017 ZL1 and just purchase a 2022 ZL1 and see where they have change the oil to OW-40. Do I need to put OW-40 in my 17

[Gunkk]

Originally Posted by hamp

I own a 2017 ZL1 and just purchase a 2022 ZL1 and see where they have change the oil to OW-40. Do I need to put OW-40 in my 17

I have for a couple years now. Blackstone labs tests show everything is fine.

[hamp]

Originally Posted by Gunkk

I have for a couple years now. Blackstone labs tests show everything is fine.

Thanks Gunkk

[UnknownJinX]

Actually, if you are not tracking your SS 1LE, 5W-30 Dexos1 is fine. If you track and DD, and you want to follow the manual's recommendation on the oil, then Mobil1 0W-40 ESP is pretty much your only choice in North America. Thankfully, you can get them for a good deal over at Rock Auto. They go for US$7-ish per quart before shipping, and RA shipping generally isn't too bad IMO. Motul also has a type of engine oil that's in 5W-40 and meets Dexos2, so that could be another option if you don't drive your car in the cold.

Regarding oil capacity, if you are doing your own oil change, I would personally dump in the first 8 to 9 quarts, and then slow down and check the dipstick to see how much you actually need. When I did mine, I needed 10.5 quarts to get it to full. YMMV, and usually I just fill any car I own with a quart less than the recommendation before checking the dipstick to see if I actually still need more.

As for when to change the oil, I concur that you should just follow OLM. 3k miles is pretty obsolete nowadays unless you run conventional/mineral-based oil or you track the car like crazy. Any good synthetic oil will last more than 3k miles. I usually just toss those stickers right away if I get them after service.

I changed my rear end oil at 500 miles once, and then I think 2000 miles. I use Motul Gear 300 LS, and I have no issues with it, but some people seem to prefer sticking with the OEM AC Delco stuff. The latter will be the safest choice, though again, Motul hasn't caused any issues. Just make sure you do get the LS variant if you do want to try it; there is a non-LS variant that's yellow/clear. LS variant is green.

[Gunkk]

Originally Posted by zxspeedspec

I will say you should check your dipstick. 10 quarts is generally half a quart too much since the last quart doesn't fully drain. It's probably not enough to cause head gasket issues, but depends on how aggressive you get with your driving.

Agree on using the dipstick. Not every car is lifted the same way, so there's likely a bit of variation. My garage has a very slight rake for drainage and I lift my car equality on both front sides with a pair of jack stands, so there's a good slope for the oil to drain toward the plug outlet. For me 10 complete quart bottles is exactly what I need, whether I pre-fill the filter or not. No more and no less. But yeah checking the stick at 9-1/2 quarts is always a good idea.

Originally Posted by hamp

Thanks Gunkk

Ya mon.

Here's the latest report if you want to see for yourself. You can see when I changed to 0w40 ESP Formula in the Boron numbers. Before that I used 5w30 Mobil1, Valvoline and Supertech without issue. You can see Blackstone's comments about it in the previous tests results I posted in the same thread: no concerns either way.

But when Chevy changed their recommended oil fill, so did I. I live where it stays warm year round so I'm not concerned about the slightly higher viscosity. And the data show that it hasn't done the car harm. None of the oils did TBH. I don't care about the extra $50 once per year and would rather go with Chevy's engineering recommendation over what I can pull out of my ass. Besides, I got a new oil fill cap out of it: https://www.amazon.com/ACDelco-FC265.../dp/B0792NR4C6

[Eric10905]

"Mobil1 0W-40 ESP is pretty much your only choice in North America. Thankfully, you can get them for a good deal over at Rock Auto."

Hey guys, been asked before, but these days the times are a changing: If you are using Mobil 1 0-40 ESP, where are you finding it? I just had to order from Amazon....Just curious where you're finding it these days...

[ctrlz]

Originally Posted by MR's 2SS

I've read that GM only recommends 0w40 because it gets higher MPGs. I find that believable.
I got 5w20 by accident one time and I got more than 1 MPG better mileage with a 6.2 that averages in the 13s.

Makes sense to me that the 20 weight oil would offer better fuel economy (slightly) compared to the 40 weight.

I think the main argument for the 0w-40 is protection for BOTH street and track use. For my purposes I'm sticking with the much cheaper Valvoline 5w-30 (dexos 2) which amazon delivers to my door at a better price than wal-mart.