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beau11x

6.2L gas issues

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My 2012 denali OM on page 9-6 "Driving and operating section says the recomended octane gas is 87. I get around 16 mpg in this balmy mich 50 degree weather.

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Interesting how a 6.2 w/10.5:1 compression ratio in 2011 can go from 91 recommended (mine) to 87 in 2012. But then again, I've always wondered how the 3.6 in my wife's '09 Traverse can have a 11.4:1 compression ratio and recommend 87, or even how my '95 Caprice cast iron LT1 could have a 10.5:1 comp ratio and run just fine on the recommended 87.

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I have noticed that I get better mileage when running 91 or higher. 87 octane gives me the worst gas mileage.

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I find claims that people increased HP and improved fuel economy at the same time to be dubious.

 

 

I agree, with one caveat. It's possible to improve "torque delivery" at heavy throttle, and to give "quicker" delivery, while also tuning low and mid throttle driving parameters. If a person makes use of the heavier throttle, mpg will go straight down. That said, I wouldn't use most of the handhelds if you gave them to me.

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I use 87 octane 100% gas in my 5.3 and if I drive 60, I can get 19-20 hwy. In the city I average 16-17 being good. If I throttle it everywhere and not baby it I will get 14-16 avg.

 

I have homemade intake and magnaflow 14" muffler.

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I use 87 octane 100% gas in my 5.3 and if I drive 60, I can get 19-20 hwy. In the city I average 16-17 being good. If I throttle it everywhere and not baby it I will get 14-16 avg.

 

I have homemade intake and magnaflow 14" muffler.

 

My 2012 denali OM on page 9-6 "Driving and operating section says the recomended octane gas is 87. I get around 16 mpg in this balmy mich 50 degree weather.

 

Just checked the owner's manual on your truck as well and this is, again, what I came up with........

 

"If the vehicle has the 6.2L V8 engine (VIN Code 2), use premium unleaded gasoline with a posted octane rating of 91 or higher. You can also use regular unleaded gasoline rated at 87 octane or higher, but the vehicle's acceleration could be slightly reduced, and a slight audible knocking noise, commonly referred to as spark knock, might be heard. If the octane is less than 87, you might notice a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you could damage the engine. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service."

 

I use 87 octane 100% gas in my 5.3 and if I drive 60, I can get 19-20 hwy. In the city I average 16-17 being good. If I throttle it everywhere and not baby it I will get 14-16 avg.

 

I have homemade intake and magnaflow 14" muffler.

 

5.3's have no need for premium fuel and aren't even been discussed here. 6.2 L9H's are.

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Chevy tech

 

What page in the manual would this be on? I checked my manual again and it says differantly. This concerns me. I bought this truck in oct 2011, so I assume it is an early 12.

 

Thanks

John

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Well, here is another version I found when I googled 2012 manual.

 

 

9-74 Driving and Operating

 

 

 

Vehicles that have a FlexFuel badge

 

 

 

and a yellow fuel cap can use either

 

 

 

unleaded gasoline or ethanol fuel

 

 

 

containing up to 85% ethanol (E85).

 

 

 

See Fuel E85 (85% Ethanol) on

 

 

 

page 9?76. For all other vehicles,

 

 

 

use only the unleaded gasoline

 

 

 

described under Recommended

 

 

 

Fuel on page 9?74.

 

 

 

Recommended Fuel

 

 

 

Use regular unleaded gasoline with

 

 

 

a posted octane rating of 87 or

 

 

 

higher. If the octane rating is less

 

 

 

than 87, an audible knocking noise,

 

 

 

commonly referred to as spark

 

 

 

knock, might be heard when driving.

 

 

 

If this occurs, use a gasoline rated

 

 

 

at 87 octane or higher as soon as

 

 

 

possible. If heavy knocking is heard

 

 

 

when using gasoline rated at

 

 

 

87 octane or higher, the engine

 

 

needs service.

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Again, for the sight impaired

 

 

9-74 Driving and Operating

Vehicles that have a FlexFuel badge

and a yellow fuel cap can use either

unleaded gasoline or ethanol fuel

containing up to 85% ethanol (E85).

See Fuel E85 (85% Ethanol) on

page 9?76. For all other vehicles,

use only the unleaded gasoline

described under Recommended

Fuel on page 9?74.

Recommended Fuel

Use regular unleaded gasoline with

a posted octane rating of 87 or

higher. If the octane rating is less

than 87, an audible knocking noise,

commonly referred to as spark

knock, might be heard when driving.

If this occurs, use a gasoline rated

at 87 octane or higher as soon as

possible. If heavy knocking is heard

when using gasoline rated at

87 octane or higher, the engine

needs service.

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Has anyone with a 6.2L paid any attention to the gas filler door?

 

Here is my truck

DSC00011.jpg

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That is exactly what mine states too

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Has anyone with a 6.2L paid any attention to the gas filler door?

 

Here is my truck

DSC00011.jpg

 

 

Oh, wow, man! Deja vu!!

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6.2 is great for hauling, towing, and performance. Unfortunately, you need to make over $100,000 a year if you're gonna drive it everyday. I take a Silverado Z71 6.2 over a Mercedes-Benz.

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Everything I have posted is out of the GM electronic copy of the owners manual. I will have to look it up in my own personal paper copy, that came with my personal truck, to verify the same.

 

On another note, I'm pretty sure that you won't get this kind of results with ANY 6.2L L9H equipped truck if you run it on 87 octane gasoline.

 

6.2 is great for hauling, towing, and performance. Unfortunately, you need to make over $100,000 a year if you're gonna drive it everyday. I take a Silverado Z71 6.2 over a Mercedes-Benz.

 

See above. I make less than half that and I'm doing just fine driving it everyday, thanks.

post-84205-133588002445_thumb.jpg

post-84205-133588002445_thumb.jpg

post-84205-133588002445_thumb.jpg

post-84205-133588002445_thumb.jpg

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