While 4 wheelin in Colorado I saw 85 Octane. And 87 was the mid-grade gas never seen that before.

 

87 octane and buy from asouthwest brand " 76 union "or UNOCAL.

 

Name brand such as Shell, BP, Mobil. Always 87 octane. Higher octane is a waste of money, and will do nothing for performance with the calibration installed via the factory or dealer.
For your reading enjoyment:

[/size]Subject:[/size]
Fuel and Oil Additives - Facts and Myths/Maximizing Fuel Economy #05-00-89-072A - (10/16/2007)
[align=left]Models:
2008 and Prior GM Passenger Cars and Trucks (including Saturn)[/align][align=left]2008 and Prior HUMMER H2, H3[/align][align=left][size=4]2005-2008 Saab 9-7X[/color][/align]
[align=left]Attention:
Please direct this bulletin to the Service Manager, the Service Consultants and the Sales Staff. A copy of this bulletin is encouraged to be given to your customer as it is written with the consumer in mind. You may also post this bulletin in your customer lounge or waiting area. [/align]

[hr]
This bulletin is being revised to update model years, Top Tier fuel providers and revise the Federal Trade Commission website address. Please discard Corporate Bulletin Number 05-00-89-072 (Section 00 -- General information).

[hr]
A Statement About Fuel Economy
As gasoline prices have increased, the consumer has shifted priorities to become increasingly concerned with fuel consumption. GM is presently proud to offer over 30 cars in the U.S. with EPA highway estimates of at least 30mpg. In Canada, vehicles are rated for fuel consumption in litres per 100 kilometers. GM offers over 20 vehicles in Canada that consume less than 7.0L/100km on the highway. The information below contains reasonable and prudent advice for your dealership and the consumer to get the most from every gallon or litre of gas.
The information below is presented in two easy to understand sections:[size=4][/color]

What Not To Do: Engine and Fuel Additives, Alternate Fuels, and "Miracle" Products [align=left]
What to Do: Maximizing Fuel Economy/Minimizing Costs [/align]
WHAT NOT TO DO: Engine and Fuel Additives, Alternate Fuels, and "Miracle" Products
Various unproven products to improve vehicle fuel economy have been reported ranging from magnets that align molecules to chemical combustion improvers.
Most products claiming to provide benefits are based on unsubstantiated claims. Those that do present "scientific" results generally either have too little supporting data to be conclusive, have not conducted experiments in a controlled fashion, or cannot be substantiated by anyone else but the product's manufacturer.
The U.S. Federal Trade Commission summarizes results for products tested by the federal government at http://www.ftc.gov/bcp/edu/pubs/cons...tos/aut10.shtm. A review of the list shows that the majority did not work, and for those that showed some effect, the benefit was too small to be cost effective.
Harmful Ideas That May Damage Your Vehicle and Increase Emissions
One more recent poor idea to improve fuel economy that should not be attempted is to blend either kerosene or diesel fuel into gasoline. Why? Both kerosene and diesel fuel are distillate fuels meant for use in compression ignition engines, not spark ignition engines. They have very low octane and since they are heavier (higher density) than gasoline, they will cause heavy engine deposits and degradation of engine oil.
Notice:Never put Kerosene or Diesel Fuel in your Gasoline Engine vehicle. This may result in inconsistent performance and permanent damage to your vehicle that is not covered by your New Vehicle Warranty.
Chemicals that are normally used as solvents also should not be used. These include acetone, ketones, and methanol. These solvents can be incompatible with your vehicles rubber or sealing components, and may dissolve the

 

Great info f5fstop. I wonder why Sunoco only got certified for Canada, and not the US?

Another thing to note, due to effects of pipeline transport, there is a little bit of grade-to-grade mixing at the interface between grades. So if there is a batch of 92 octane next to a batch of 87, they'll switch storage tanks before the mixing area reaches the destination, and minimally upgrades the 87 octane product (depending on the receipt tank anywhere from .1 to .3 octane). That's why at the pump you see on the stickers "at least 87 octane"

 

I saw this at the Hummer dealership. BTW f5fstop, I bought my 3 from the same dealer you got yours from. Thanks for the info. I was waiting for the bru haha that always develpoes in these "what octane" threads, I guess you chilled that out.[&:]Dang nabit.

I use Marathon cuz it has STP and Richard Petty uses it in his car, so we know it must be good. New STP-Richard Petty TV Commercial

 

I understand the pipelines across the USA from refinery to refinery and to tank farms, loading depots, etc. However, I was always told that the iso-octane and heptane were added at the transport truck fill-up. Regardless, I read your post and then went and filled-up on the way home and my local Shell says 87 Octane, nothing to state it could he greater. I wonder if that could be only in certain areas?

 

I use Marathon sometimes. So, how do you know where I purchased my Hummer from?Do they have my photo on the dart board?

Talking about dealers, I have to get my 3 up to the dealer for some service. Back door switch, park brake cable, new washer/coolant bottle (leaked like crazy in Utah this year and they have a bulletin for a new assembly), and both of my fogs are broken (wiggle like crazy, the adjustment rod's plastic fastener on both assemblies has cracked.

 

Thanks for all the feedback. Thus far, 2-1/2tank fulls and I have been running 87 octane, Shell, 7-11 (Citgo, I think) and just filled at BP. Mileage thus far has averaged 17.6 mpg.

 

I'm running 89 octane from 76.

 

J R's Friendly Hummer, Romeo Plank and M59. No dart board, mabey by the hockey sticks. Remember, we're still waiting for a Happening other than a blood drive?
They got a ton of inventory right now. Which is a good thing????? I guess.............