2015 yukon denali gas?

[ajeagle6921]

What gas are you other 2015 denali owners using in your yukon? I have been using 89 octane and just wondering what others are using. Thanks.

 

[Db239]

I use 89 and got almost 21 mpg on my trip to Colorado...over 2000 miles round trip. 16ish in the city normally using the same gas.

 

[hosseface]

87. 20+ mpg no problem.

 

[zolt11]

I have only used 89 too.

 

[ecanem]

Octane and fuel economy have no correlation. 87 octane isn't worse for the trucks and paying for higher is basically a waste of money.

The only times I get higher octane is when the car requires it due to a high compression engine.

 

[Reels]

Octane and fuel economy have no correlation. 87 octane isn't worse for the trucks and paying for higher is basically a waste of money.

The only times I get higher octane is when the car requires it due to a high compression engine.

I will let you argue this with GM. From the manual.

"Use premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 91 or
higher. Regular unleaded gasoline
rated at 87 octane or higher can be
used, but acceleration and fuel
economy will be reduced, and an
audible knocking noise may be
heard."

I see about 10% better MPG with 91 verses 87 on my 2013 Denali.

 

[ecanem]

I will let you argue this with GM. From the manual.



"Use premium unleaded gasoline

meeting ASTM specification D4814

with a posted octane rating of 91 or

higher. Regular unleaded gasoline

rated at 87 octane or higher can be

used, but acceleration and fuel

economy will be reduced, and an

audible knocking noise may be

heard."



I see about 10% better MPG with 91 verses 87 on my 2013 Denali.

I don't have a Denali manual. If that's what it says then 91 should be used as the Denali has a higher compression. The regular yukon doesn't need 91 and using 91 will not improve performance.

My point still stands that using a higher octane on a non high compression engine is a waste. Using 91 doesn't give you improved performance on a high compression engine, it's the standard, using 87 reduces your performance due to detonation.

 

[Reels]

I forget we have two engine types. That makes sense, thanks.

 

[ecanem]

That makes sense.

Also. Given your quote. There shouldn't be a question for anyone. Use 91 on your Denali, it would be detrimental to the engine otherwise.

 

[ajeagle6921]

If I use 89 would it really be that bad?