Does a 2024 Z51 with 6.2 require premium fuel?

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steiny93

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the 6.2 absolutely 100% does not REQUIRE 91 octane; it'll adjust timing to prevent engine damage

per the owners manual
Recommended Fuel (6.2LV8 Engine)Premium unleaded gasoline meeting ASTM specification D4814 with a posted octane rating (R+M)/2 of 91 or greater is recommended. If unavailable, unleaded gasoline with a posted octane rating of Driving and Operating 30587 may be used, but will result in reduced performance and drive ability. If heavy knocking is heard when using gasoline rated at 91 or greater, the engine needs service. Do not use any fuel labeled E85 or FlexFuel. Do not use gasoline with ethanol levels greater than 15% by volume.

octane rating is a measure of fuels resistance to detonation (not energy or cleanness or anything else)
if you run less then 91, under load it'll start to knock so the truck will adjust timing which lessons performance but saves the engine

does 91 vs 87 improve mileage; maybe, empty on a cool day, nope; hot day towing, perhaps
does 87 vs 91 hurt the 6.2; no
 

swathdiver

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the 6.2 absolutely 100% does not REQUIRE 91 octane; it'll adjust timing to prevent engine damage

per the owners manual
Recommended Fuel (6.2LV8 Engine)Premium unleaded gasoline meeting ASTM specification D4814 with a posted octane rating (R+M)/2 of 91 or greater is recommended. If unavailable, unleaded gasoline with a posted octane rating of Driving and Operating 30587 may be used, but will result in reduced performance and drive ability. If heavy knocking is heard when using gasoline rated at 91 or greater, the engine needs service. Do not use any fuel labeled E85 or FlexFuel. Do not use gasoline with ethanol levels greater than 15% by volume.

octane rating is a measure of fuels resistance to detonation (not energy or cleanness or anything else)
if you run less then 91, under load it'll start to knock so the truck will adjust timing which lessons performance but saves the engine

does 91 vs 87 improve mileage; maybe, empty on a cool day, nope; hot day towing, perhaps
does 87 vs 91 hurt the 6.2; no
You know how it adjusts timing? AFTER it detects detonation. You pull off from a stoplight and it knocks, pulls timing. You give it some gas to pass a slow poke, it knocks and pulls the timing. Do this 500 times a morning and evening and you soon have a worn out motor with busted rings and pistons at around 100K miles.

These trucks are so well insulated that it is almost impossible to hear detonation and pinging with your ears. You can however watch it on a scan tool with live data.

I challenge fellas all the time to prove me wrong with the live data, no takers yet.
 
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lt1gmc

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If you can't afford the fuel, get another vehicle. Absolutely ridiculous to spend 80,000 + on a vehicle
then try to pinch pennies and risk ******* it up.
You are right except I can afford the fuel, just not going to pay the ridiculous addition cost every fill up. The purpose of the question is to know it premium is required. I'm not going to buy it if so. Not pinching pennies, but not knowing the future I'm not going to lock myself into another premium only fuel vehicle, I already have 5. When premium was only .20 per gallon more was not such a big deal.
 

WalleyeMikeIII

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You are right except I can afford the fuel, just not going to pay the ridiculous addition cost every fill up. The purpose of the question is to know it premium is required. I'm not going to buy it if so. Not pinching pennies, but not knowing the future I'm not going to lock myself into another premium only fuel vehicle, I already have 5. When premium was only .20 per gallon more was not such a big deal.
The owners manual says premium is recommended. But, I feel you will shorten the life of the engine if you run 87.

You said you want to have longevity, if you don’t want to buy premium, get the diesel, for sure. That’s a great setup. I strongly considered it…but live where I have a short (5 mile commute) and in the winter weeks of never above 0F for temperature in Jan/Feb. So, didn’t think those short trips in the cold were a good application for the diesel.

The smile factor is big on the 6.2 when you put your foot in it. I had 5.3 in all my previous rigs, and the extra HP and Torque in the 6.2 makes me smile every time I pass a car on a 2 lane!
 

swathdiver

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You are right except I can afford the fuel, just not going to pay the ridiculous addition cost every fill up. The purpose of the question is to know it premium is required. I'm not going to buy it if so. Not pinching pennies, but not knowing the future I'm not going to lock myself into another premium only fuel vehicle, I already have 5. When premium was only .20 per gallon more was not such a big deal.
$20 a fill mean that much to you in this day and age with a $80K car? You know that a $20 is the new $5 bill right?

Is the extra 65 horsepower worth it to you?

So with 5 cars taking high octane gas how is one going to make a difference? At that, you ought to put in a 300+ gallon tank and buy in bulk!
 

Polo08816

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Well recently there has been a common theme of main bearings letting go on the crank due to bad clearances. If you search around you'll find an amount of both issues cropping up. Diesel vehicles also present a certain number of quirks over time, but I'm on my 4th one and by and large they have been very dependable. The LM2/ LZ0 combination if you look at most forums, really isn't that busy at all. A few crop up with issues or major issues, but by and large this format has been the best for these large vehicles. I personally bought an extended warranty for mine that will last me for as long as I own it. Right or wrong it will cover most any issues that come up after warranty and I don't lose any sleep over what just might happen.

Sad to see that the Escalade is dropping the diesel format for the future. I thought about maybe buying one as one of my last great vehicles in 25 or 26....

Also, if you are locked into premium, you will be paying the absolute highest price for fuel for the life of the vehicle @ an avg of 15 mpg. Diesels worst mileage is about 22 if you are pounding it around town...The gap from reg to prem could easily expand to 2.00 a gallon in a few years... What would stop them?

As far as sensors go, they certainly "can" be a problem, but they usually sort themselves out during the 3/36 period. If I had to throw 3-500 bucks at my vehicle a few times over its life beyond regular maintenance, that's certainly not a showstopper to me.

We test drove a 2024 Yukon XL SLT with the LM2. The Duramax powertrain far exceeded what we expected as far as refinement to the point where it's under serious consideration. We have to test drive a 6.2L in the future as well although it's not offered in the SLT trim. We'll probably opt for the AT4 if we decided to go with the 6.2L.

We aren't basing our decision on fuel costs. It's really about whether the Yukon XL might end up being our primary tow vehicle in which case the exhaust braking could be useful. Or whether we enjoy the extra power of the 6.2L L87 and the linear feel of a NA V8.

I would expect the L87 powertrain to be easier to service as there's less going on in the engine bay. I don't expect the main bearings to be a persistent problem if the design hasn't changed. I do expect the lifters to be a re-occurring problem as this is a design flaw.
 

TXt3rr0r

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I'm not saying it's a good idea to do so, but my father drove his zr2 silverado for 8mo and never put a drop of premium in it, and he has a very heavy foot, never resulted in any issues in the 35k miles he had it
 

K2 Kaiju

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Swathdiver is so right when he claims the timing pull begins AFTER you already do a little damage. Gotta haul a load in the heat? Gotta whip into traffic? Gotta tow a trailer? Gotta haul ass from your hoe bag's ex chasing you in a 5.3? You can't change what already in the tank in those situations. As for diesel - cheap now, but it has been over $1 more than regular for the past few decades around here until recently. Premium is 40-60 cents. If you are in doubt, tune your 6.2 so you know it needs high test every time and really beats that hoe bag's ex's truck...
 
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Marky Dissod

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Anyone else think the censorship of words here is a little over sensitive?
Hoe bag should not be censored.
Always thought the reason for the censorship was that we were all a bunch of children,
and we had to protect our parents from finding out vulgarity is par for the course for us?

Was that not the reason? 'cause if it's not, then what's the purpose of this censorship bullschidt?

Back on topic ...

If you drive a 6.2L with 87 like a jack@$$, you will find out what the difference between cast and forged pistons, sooner or later ...
 

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