New guy here.
I'm buying a 2019 colorado. It has the 3.6L V6 LGZ I think. Anyway it has 11.5:1 compression ratio and says it runs on regular gas.
I can't find any info on what octane the engine is rated for? To me regular is 87 but GM has a standard of 91 octane I heard and perhaps their "regular" is considered to be 91 octane.
Can someone verify the octane requirement for this enigine?
My chevy cruze needs 91 but is turbo charged.
Thanks

Burn a little 87 and see if it pings. If it don't ping you are good with 87.

The 3.6 can run on just about any gasoline and E10 sold in the US. If it detects detonation for whatever reason, including low-octane fuel, it just retards the timing.

. . . and check this out from the 2019 Chevrolet Colorado owner'* manual:

At higher altitudes (like 4,000' and up, high plains, Rocky Mountains etc.) you'll find that the selection drops by a few octane across the board. Instead of 87/89/91 you'll see 85/87/89 or thereabouts. It'* okay to run 85 in these while you're up at altitude. The difference up there, on naturally aspirated engines, is that there is less air in the cylinders on each intake stroke, therefore less cylinder pressure on the compression stroke, therefore less cause to knock. How do I know this for sure you ask? I have over 200,000 miles of experience with a GM 3.6 running that swill with no issue. Again, the computer just backs the timing down when as needed . . . and it just feels a little more anemic while this is happening.

And as always, think of it this way: If your Colorado were a rental car, it would get the cheapest stuff everywhere it went . . . and it would be fine.

Yes I'm well aware of the higher elevation issues but I'm at +/- 700'
Pick it up thursday and the owners manual is in the glove box. Test drove it saturday and made the commitment to buy.
My 2013 turbo cruze adjusts for lower octane and gets less MPG if I use 87 vs 91 recommended. When I first bought it I ran 87 not knowing turbos require higher octane while not getting the 26/38MPG they said. 6 months or so later I found out 91 is recommended. With that said if I use 93 the cruze exceeds the 26/38 MPG but the cost isn't worth it when going by percentage increase in MPG vs per gallon difference.
Anyway I'll be reading the owners manual to figure out how to use the computer system that 90% of it I'll probably never use. I'll look for the octane rating you posted also.
One interesting thing I saw when turning the engine off after test drive it said look in the back seat. LOL I assume so there'* no kids back there to cook in the sun I suppose. lol
Thanks guys!!!

Yeah, if it detects any doors opened for the rear seating area while the ignition is on it will say that.

But the doors were not open?
I'll check into it when I pick it up. Shouldn't it say door ajar? My cruze shows door, hood or trunk open. Either way no big deal.

If any of those doors were ever opened while it was awake to notice, even if they were closed completely afterward, it will do this. I think this includes some amount of time before the vehicle is started, possibly starting from when the vehicle is commanded unsecure when you unlock with a fob or open a door with a key then turn on the ignition. It says "oh look at that, they put something in the back seat, and that something could be their precious baby/dog/cat/iguana/wedding cake so I should keep this in mind to tell them when they shut off the ignition next time."

Well . . . actually . . . it sets a flag by turning a bit from 0 to 1 and then does a check of this bit when the ignition is turned off later. I just like to think it cares about our pet hamsters/turtles/children/cockatoos/5.25" floppy disks/cubes of beer.

I think I saw a setting in the vehicle settings where this can be turned off, but I left it on. This was on several rental cars I've had over the years that were Colorados and Canyons.

Well the back door was open while engine running when I was inspecting the vehicle before test drive.
This modern technology crap I mean stuff has gone way too far.
This reminds me how much I love my '66 chevelle.

I tend to agree. I know it probably happened back in the day, but it seems like over the last decade or so there has been a surge in people accidentally forgetting kids in cars. Personally I have to wonder if the current trend towards continuous distractions is related.

I don't think it so much about forgetting, but too lazy to bring them into the store then when something goes drastically wrong they claim they "forgot" to avoid a lengthy jail time for child neglect.