I understand that G37S requires premium gas. So 87 is completely ruled out.

so can i put a 91 instead of 93. Or is it a must to put a 93 to get a good gas mileage and power??

Is there a difference in gas quality from different gas station brands? Like if I buy 93 at Chevron/Shell and 93 at Costco , is it still the same 93?

Does anyone here fill gas at Costco. What is the premium gas in Cotsco and best suited for G37?

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2010 G37S | Navigation and Premium | Black on Black

 

personally, I will only put 93 in my G. Are you hurting it by using 91? Probably not. And in some areas, 91 is the highest octane they have, so there is no choice.

Different gas stations WILL result in different MPG's and different miles/tank slightly. I used to drive the exact same roads the exact same speeds and I tested out different stations (with the same octane) and I DID notice just slight variations in them. I guess you could attribute it to just a mind trick, but I think the different additives stations use does manifest a small difference. Is it enough to worry about? Not at all

 

To deal with California, "premium gas" is rated at 91 or higher. You can run 91 as your car, from the factory, is tuned to run 91. It's technically tuned to run 87 as well and many on here use 87 as their regular gas for all fill ups and have zero issues. It's a running debate.

I personally have had nothing but issues with running 87. Everything from horrible gas mileage (<12mpg), noticeable lack of power, and even an SES light one time.

Costco gas is the same gas that Sam's Club has, Speedway, Thortons, USA Gas, and any other cheap-o-brand that you can find.

BP, Shell, and Chevron are the only three that I know of who actually put and back up their detergents additives but even then it's hard to say.

I find that my car runs the absolute best on Shell V-Power 93. My grandfather who has a Dodge Caravan and quite literally travels the country says he as well gets better gas mileage from Shell. He actually stopped using BP (his old favorite gas) when he saw how well his mileage became from Shell. He's super **** and logs every mile he has ever driven in the last 25 years so I trust him when he says he could tell the difference between the two.

I would just stick to 91 or 89 at the very latest. It's not much more money per fill up. Hope this helps!

 

Thanks for the info guys.... I have a new car n it has just run 600 miles. I don remember putting a 91 or 93. I went for 89 , which i guess i should avoid. I noticed a mileage of 17-18 per gallon on highways/city..

Is that very less for a new car?

 

Chevron or Mobile premium only for me. 91 octane for California.

 

Your car will make ok gas mileage until it's broken in so just give it time.

 

I prefer Shell VPower for its superior cleaning attributes.

 

ive been on the same issue OP. i started using exxon's supreme93 for the past three weeks. starting next week im going to try shell's vpower. then ill be able to see which one i *think* feels nicer

 

Shell VPower 91 here, too!

 

I've notice lukoil is giving me 20.2mpg for a while now. And that's city driving. Gonna stick with that for a bit and then switch to shell cause of their "nitrogen" gas commercials lol.

 

Can only get 91 in Kansas.....

 

I only use Shell vPower 91 octane. Reason being that it gives the best gas milage on my car.

 

she is definitely not pumping 91.. 87 for sure..

 

I only use SamsClub or Shell 91 octane, those are the only two stations in my town that doesn't switch to Ethanol in the winter months. Ethanol sucks in our Gs, I get 27 mpg on the 91 but will dwindle to 19-21 mpg on the Ethanol regardless of brand. This also applies to ANY Ethanol that I've used from New Mexico, Kansas, Colorado, Arizona & Nevada. Sure wish they'd ban that crap!

 

You can get 93 in the bay area?

I just stick with Chevron 91 (cheapest and closest gas station to home) or any other name brand 91. I do use costco if I happen to be there on an empty tank.