Does a 2024 Z51 with 6.2 require premium fuel?

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Marky Dissod

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You might not notice a difference but the computer is probably pulling timing back, especially when air temps get hot.
If you don't run the recommended fuel, drive it like your grandmother.
If driven hard, if the engine is working or playing hard with 87, the pcm / ecm IS responding to detected knock AFTER IT HAPPENS by pulling timing back, and possibly adding (wasting?) fuel to cool the cylinders.
The pcm / ecm NEVER learns this. It never predicts or avoids knock.
It only responds to it quickly enough for y'all to deceive yourselves into saying schidt like
'My 6.2L doesn't knock on 87, regardless of how I drive it.'
Put it on a realtime scanner, learn something new.
As been said by previous people, you probably won't hear it knocking, unless under a higher load,
but the computer IS dialing back the timing.
This is another way of saying that you're wasting money on 87 instead of using 91.
Yes, 91 costs more, but MpG would improve by enough to offset the price in most cases.

If not, try E85 - especially if it's at least 25% cheaper than 87.
It has pretty good knock resistance, and you'll get back much of the power lost to 87.

If you can't try E85, and you won't try 89 or 91 octane,
thanks in advance for breaking the engine I was gonna swap into my old Tahoe ...

note: this forum's software redacted something that really did not need redacting.
The redaction policy is more peurile than the thing it tried to redact.
 
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Vladimir2306

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If driven hard, if the engine is working or playing hard with 87, the pcm / ecm IS responding to detected knock AFTER IT HAPPENS by pulling timing back, and possibly adding (wasting?) fuel to cool the cylinders.
The pcm / ecm NEVER learns this. It never predicts or avoids knock.
It only responds to it quickly enough for y'all to deceive yourselves into saying schidt like
'My 6.2L doesn't knock on 87, regardless of how I drive it.'
Put it on a realtime scanner, learn something new.This is another way of saying that you're wasting money on 87 instead of using 91.
Yes, 91 costs more, but MpG would improve by enough to offset the price in most cases.

If not, try E85 - especially if it's at least 25% cheaper than 87.
It has pretty good knock resistance, and you'll get back much of the power lost to 87.

If you can't try E85, and you won't try 89 or 91 octane,
thanks in advance for breaking the engine I was gonna swap into my old Tahoe ...

note: this forum's software redacted something that really did not need redacting.
The redaction policy is more peurile than the thing it tried to redact.
E85 is prohibited for use on these engines
 

Vladimir2306

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I think for your application, get the 3.0 Duramax and don’t look back.

quick math, using these assumptions:
25k/year at 65% Highway/35% city.

So, 16,250 Hwy and 8,750 city miles.

Diesel, assume 28MPG Hwy, 20 City
Gas, Assume 19 MPG Hwy, 14 City

Diesel = 580 gal Hwy, 437 gal City = 1017 Gal
Gas = 855 gal Hwy, 625 gal City = 1480 Gal

Wild Card is pricing, but let’s use what I saw at the pump 2 hours ago when I filled up.
Diesel = 3.499
93 Octane Gas = 3.799

Annual Fuel Cost:
Diesel = $3558
Gas = $5622

Assume DEF to fuel 50:1, so 20 gal of DEF at $5/gallon = $100

Let’s call a gas oil change $110 and a diesel one $210.

Assume you need three a year:
Diesel = $660
Gas = $330

Then cost for fuel, oil, DEF
Diesel = $4318
Gas = $5952
Why count Gasoline 93? For the 6.2 engine, 91 gasoline is used.
In general, it is clear that Diesel is more economical, but diesel does not have that Charisma, that Character, like a V8, it accelerates like a grandfather. So if you are buying a car for leisurely travel, then yes, Diesel is an excellent choice. And if you want emotions, then only 6.2))
Well, diesel is not the best choice in cold regions.
 

WalleyeMikeIII

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Why count Gasoline 93? For the 6.2 engine, 91 gasoline is used.
Most US gas stations sell unleaded in three grades:
1) Regular — usually 87 Octane
2) Mid Grade — Usually 89 Octane
3) Premium — usually one of 91 or 93 Octane.

Often “premium” is priced the same whether 91 or 93 octane…

These numbers are the “Anti Knock Index” numbers, but the RON that Europe uses.
 

Vladimir2306

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Most US gas stations sell unleaded in three grades:
1) Regular — usually 87 Octane
2) Mid Grade — Usually 89 Octane
3) Premium — usually one of 91 or 93 Octane.

Often “premium” is priced the same whether 91 or 93 octane…

These numbers are the “Anti Knock Index” numbers, but the RON that Europe uses.
Got it, thanks) I didn’t know, I thought in the USA there were different prices for 91 and 93 Gasoline. Although $3.79 per gallon is a lot. In our country, 100 grade gasoline costs about $3 per gallon. And Premium comes out to about $2.3 per gallon. But diesel is significantly more expensive here. $2.8 per gallon
 

KMeloney

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Got it, thanks) I didn’t know, I thought in the USA there were different prices for 91 and 93 Gasoline. Although $3.79 per gallon is a lot. In our country, 100 grade gasoline costs about $3 per gallon. And Premium comes out to about $2.3 per gallon. But diesel is significantly more expensive here. $2.8 per gallon
In the northeast, it's a pretty big jump in price from 89 to 91... And then a much, much smaller jump from 91 to 93.
 

WalleyeMikeIII

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Got it, thanks) I didn’t know, I thought in the USA there were different prices for 91 and 93 Gasoline. Although $3.79 per gallon is a lot. In our country, 100 grade gasoline costs about $3 per gallon. And Premium comes out to about $2.3 per gallon. But diesel is significantly more expensive here. $2.8 per gallon
Oh, the US and State Government's love to TAX fuel. Esp the ones like CA, IL, NY, etc. My daughter spent some time in TN and fuel there was routinely $2.40-$2.70 on the same day it was $3.35 in Minnesota...And some states have harsher formulation rules to combat emissions and evaporation as well, these custom formulations can definitely vary the price. But the biggest impact is state tax.
 

Joseph Garcia

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Most US gas stations sell unleaded in three grades:
1) Regular — usually 87 Octane
2) Mid Grade — Usually 89 Octane
3) Premium — usually one of 91 or 93 Octane.

Often “premium” is priced the same whether 91 or 93 octane…

These numbers are the “Anti Knock Index” numbers, but the RON that Europe uses.
I've never seen the same price for 91 and 93 octane in NH, but different regions have different pricing scales. That being said, the difference in cost these days between 91 and 93 octane is rarely more than 10 cents per gallon in NH.
 

WalleyeMikeIII

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I've never seen the same price for 91 and 93 octane in NH, but different regions have different pricing scales. That being said, the difference in cost these days between 91 and 93 octane is rarely more than 10 cents per gallon in NH.
I can buy 93 at Sinclair for $3.699 today, 92 at Costco is 3.719, and 91 at KwikTrip is $4.099 (but the last one is Ethanol Free)
 

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