HIGH OCTANE FUEL 6.2L

Elpresidente · October 20, 2019

Bought a 2020 AT4 with a 6.2L before buying I knew it needed premium but did not know it needs 93 premium. Live in very southern Orange County the very south tip of LA. Have no access to any 93 fuel. Closest is 100 octane a very expensive option; 25 miles north through heavy city traffic. 93 octane is 35 miles away.

Have 92 octane close within a mile of home; have no problem buying premium fuel. Although what is the impact over the lifecycle of the truck running 92 versus 93?

do anyone have access to a power train engineer at GM that can comment with real data?

Its not about the fuel mileage; or the expense of higher octane fuel. More care about knocking, pinging, damage over the long term.

lt1z · October 20, 2019

Bought a 2020 AT4 with a 6.2L before buying I knew it needed premium but did not know it needs 93 premium. Live in very southern Orange County the very south tip of LA. Have no access to any 93 fuel. Closest is 100 octane a very expensive option; 25 miles north through heavy city traffic. 93 octane is 35 miles away.

Have 92 octane close within a mile of home; have no problem buying premium fuel. Although what is the impact over the lifecycle of the truck running 92 versus 93?

do anyone have access to a power train engineer at GM that can comment with real data?

Its not about the fuel mileage; or the expense of higher octane fuel. More care about knocking, pinging, damage over the long term.

91 is all that is needed.

Snakes709 · October 20, 2019

Mine runs fine on 87. I have 91 in it right now just because your get 10x air miles right now with 91. Once that promo is over, ill go back to 87.

Elpresidente · October 20, 2019

drove all my local gas stations; 10 total and only have 91 octane in a five mile radius.

Figured before i posted this that 91 would have a high probability of being fine.

how do we get Objective data on this?

Or how do we get a gm powertrain engineer to subjectively say that during development and the testing stage that the maps in the computer are designed and were endurance tested for long term 91 Octane use.

that these engines were built to detect 91 fuel. Fairly certain this the L87 does not have a octane sensor like flexfuel vechicles..

Simply do not know enough about how knock sensor microphones would be able to pickup pinging/detonation and dial the timing back.

Dialing the timing back is probably not where in the design window where one wants to be running the engine. If your already pre-detonating And your ecu has to retard your already in bad territory. Maybe the engine was designed to then run safely in “retard” Or maybe it was only designed to get best emissions under 93 and designed to run properly in the appropriate pararmeters with 91.

why i think 91 is probably safe is because this engine runs cool maybe around 180F unloaded/not towing. Probably by design to minimize detonation.

lt1z · October 20, 2019

drove all my local gas stations; 10 total and only have 91 octane in a five mile radius.

Figured before i posted this that 91 would have a high probability of being fine.

how do we get Objective data on this?

Or how do we get a gm powertrain engineer to subjectively say that during development and the testing stage that the maps in the computer are designed and were tested endurance tested for long term 91 use.

that these engines were built to detect 91 fuel. Fairly certain this the L87 does not have a octane sensor like flexfuel vechicles..

as well

91 is acceptable for any vehicle sold in North America. You can even run lower but it will effect performance as it transitions down to the low octane table. The knock sensors keep it in line.

brendon444 · October 20, 2019

1 hour ago, Snakes709 said:

Mine runs fine on 87. I have 91 in it right now just because your get 10x air miles right now with 91. Once that promo is over, ill go back to 87.

Have had 4 6.2's and always run 87, Runs no different for me

AlaskaErik · October 20, 2019

For some reason premium gas at all stations here is 90 octane. Not sure why, but truck seems to handle it just fine. Regular is 87, mid-grade is 89 and premium is 90. And we're at sea level.

Snakes709 · October 21, 2019

11 hours ago, brendon444 said:

Have had 4 6.2's and always run 87, Runs no different for me

Mine feels alot more responsive with 91, but has no issues like pinging with 87. Same thing with the wifes equinox with the 2.0 turbo. Recommends 91 but 87 is fine and 91 is alot more responsive and fast as **** for a suv

Impala_98 · October 21, 2019

I am another one that never even thought about using a different fuel I have always used 87 my 17 AT 5.3, and for the first month of having my 19 Denali 6.2 I've been using the same thing.. I started reading this and ran out to look at the fuel door to see if it was true (It is).

My question, I (think) understand the knock sensor will cause the performance to suffer under lower octane, but will it also effect the cylinder deactivation feature? Does anyone know where you can see how many cylinders you are running on my 2017 show v8 and v4 on the instrument cluster screen I can't find this on my 2019?

btw..... GM please bring back the upper door storage pockets and add wireless CarPlay thank you

Impala_98 · October 29, 2019

Update.......

So since my last post I have been using 93 from Costco (roughly the same price $2.80-90 per gallon as 87 at other stations) and the Auto Start Stop does seem to less jerky. When I have my music up sometime i don't even notice it.

I can definitely feel the difference in my 5.3 and 6.2, the 6.2 moves when you hit the petal and doesn't have the 5.3 "stutter step". Before there was a difference but it wasn't enough or me to justify the additional $$.

I have a lot of sit and wait time in the truck so I can not tell if the fuel economy improve.

btw..... GM please bring back the upper door storage pockets and add wireless CarPlay thank you

TJay74 · October 29, 2019

On 8/28/2019 at 9:18 AM, amxguy1970 said:

5 or 6 MPG? What is wrong with your truck? It should be around 1 maybe 2 mpg tops. We run 87 in our 6.2 most of the time, you would be hard pressed to tell a difference of the 15 or so hp lost and we are just over 1 mpg difference between the two octanes. If you are seeing a 5 mpg difference, your truck is broken and needs to get looked at...

This was an excellent article on comparing the different octanes in the same vehicles of different types and engines.

OP, 87 is fine if you want to save a little and you aren't pushing the truck hard in the middle of summer or towing regularly. It actually works out to saving money using 87 as the mpg penalty isn't much compared to the price savings per gallon.

https://www.caranddriver.com/reviews/comparison-feature/a28565486/honda-cr-v-vs-bmw-m5-ford-f-150-dodge-charger/

Tyler

GM has advised several times now, take the chance if you want. But if you get any type of engine damage from running 87 octane they are not and may not repair the engine. The manual was changed during the 2016 model year to say the 6.2l require 91 octane or better fuel, not recommend. The manual goes on to say while you can run a lesser octane at a reduced power and performance but that engine damage can also occur and any damage caused from not running 91+ octane or better may not be covered under warranty.

With that, I dont get why people buy the 6.2 trucks and then start skimping out on the gas. The tank is 26 gallons, even if you took it down to needing 20 gallons of gas the difference from 87 to 91 is only around $.50 per gallon or $10 per tank difference in price. Top it off even on 91 octane and in any remote type of nice weather and the 6.2l engine is prone to engine knock due to the aggressive timing map in the ECM. It only takes a couple of knock events to get the ECM to drop into the low octane timing map and reduce power and performance.

Now with the cooler weather can you run 89 and maybe get away, sure you can but unless I had some data logs I wouldnt do it until I knew for sure that the engine was seeing any knock events.

I dont pay your truck payments, so do as you want. Pretty expensive gamble to take just to save $5-$10 per tank on gas.