5.3 vs 6.2 octane

[h2100]

Hello All,

I'm an owner of a 2010 Tahoe with 185,000 (middle aged!) and will be upgrading in the next 3-4 months to a new-to-me model. Probably a 2017-2018 Tahoe/Yukon/Escalade. I have a 23 ft boat that I travel with 6-7 times a year plus other trailers many time. The 5.3 does good enough but it does work hard. An Escalade (Denali too) is interesting to me since the 6.2 comes standard.

Question, it seems many web pages/articles indicate the 6.2 needs 92 octane to run properly. Who has experience here?

Is this true?? Please share thoughts.

 

[avalonandl]

92 Octane is RECOMMENDED. I would absolutely use it when you tow. Many people drive these vehicles on regular or mid grade.

 

[Curt Hibbert]

When I picked my 2012 Denali up at the dealer, (18 months ago) I had to fill it up first thing. It was so empty I was worried about running out so I stopped at the nearest gas station and filled it up with 87 octane because that station did not carry premium. I was really so disappointed with the way it ran. When I had the cruise on the highway there was a lot of downshifting to maintain speed. Next tank I filled it up with premium and that behavior stopped. It runs so much better on high octane. I ran E-85 for a few tanks just to see how it ran. Runs really well on that too! About a wash price wise (between premium gas and E-85) because of the hit to mileage though.

 

[Joseph Garcia]

I have been told that the 6.2 was originally designed for use with a higher octane gas, but I don't have anything factual to back that up.

Personally, I rune 93 octane gas exclusively in mine, and I have a Black Bear performance tune designed to run with the 93 octane specification.

 

[Doubeleive]

I have never noticed a difference running any octane, in performance or mileage. I have noticed a difference in how much it cost, that being said I do run at least mid-grade in my 6.2l and sometimes 92 simply because it is recommended. and that being said I usually have my foot in it either way no noticeable difference while driving AT ALL.

 

[BG1988]

Hello All,

I'm an owner of a 2010 Tahoe with 185,000 (middle aged!) and will be upgrading in the next 3-4 months to a new-to-me model. Probably a 2017-2018 Tahoe/Yukon/Escalade. I have a 23 ft boat that I travel with 6-7 times a year plus other trailers many time. The 5.3 does good enough but it does work hard. An Escalade (Denali too) is interesting to me since the 6.2 comes standard.
Question, it seems many web pages/articles indicate the 6.2 needs 92 octane to run properly. Who has experience here?

Is this true?? Please share thoughts.

I run 91 oct 6.0L v8 VVT gen4


honestly it makes quite the difference as well as significantly improved mileage.. over 87oct baseline I'm able to manipulate the DFCO better resulting in a significant boost in mpg... you cant do that with 87octane

 

[thompsoj22]

08 yukon denali 6.2, i bought it 2 years ago at 125k miles, im now at 141k miles chevorn/techron premium exclusively! yea i use the chevron card and save a few pennies that way. F'it, you cant take it with you! and the compression ratio stipulates 91 octane in the manual. can you run regular? absolutely.

 

[Foggy]

91 is best. It is due to the compression ration, cam timing, spark timing etc.
It will run fine on 87, but the knock sensor will be triggered quite a bit..
This then tells the computer to make reductions in timing and cam timing VVT.
So you will lose fuel MPG and HP for sure.
Def always run good premium if you are towing or have heavy loads

 

[swathdiver]

Hello All,

I'm an owner of a 2010 Tahoe with 185,000 (middle aged!) and will be upgrading in the next 3-4 months to a new-to-me model. Probably a 2017-2018 Tahoe/Yukon/Escalade. I have a 23 ft boat that I travel with 6-7 times a year plus other trailers many time. The 5.3 does good enough but it does work hard. An Escalade (Denali too) is interesting to me since the 6.2 comes standard.

Question, it seems many web pages/articles indicate the 6.2 needs 92 octane to run properly. Who has experience here?

Is this true?? Please share thoughts.

Seen lots of Denalis with broken pistons from running low octane gas in them. The 5.3 in the later generations make a lot more power than yours, test drive both engines. I run high octane fuel in everything, even my lawn mower and generator, more power more power!!!!

 

[Larryjb]

How heavy is the boat you are towing?

My 2002 Tahoe works hard to pull our trailer up hills. Loaded, we had a total loaded weight (truck, trailer, people, cargo etc) of about 10,000 lbs. The engine worked hard and tended to overheat in the summer heat unless I turned off the AC. I know there are many factors involved such as transmission coolers, external oil coolers, etc etc etc. But, the engine did work hard pulling that load.

A couple of years ago, we towed our trailer with our 2008 4.6L Ford Explorer. It has VVT, and a 6 speed transmission. The trucks are similar in weight. This engine, in spite of being smaller, pulled the trailer with greater ease. We didn't have to turn the ac off going up the CA Grapevine.

I'd say if you are alright with the 5.3 in your 2010 5.3, you will be even happier with a 2018 5.3. However, I suspect that you'd have even more fun with the 6.2.