In cali, people join costco just for the gas discount, averages 60 cents less per gallon for top tier, sometimes a little less sometimes a little more, yes more then 60 cents per gallon, but averages 60 cents cheaper then top stations. For some reason shell is even more, so like 80-100 cents cheaper then shell around here. I never paid for my redline si-1, it pays for itself by using costco gas. 7-8 bucks per tank savings. However, it isnt always good news, because gas is so cheap, it is like the 70's every single time you want gas, lol. Yes, a line 4-5 cars deep all hours the thing is open. Once is a long while you will have no line, and you always ask yourself what is going on today there is no line at costco gas.
I too am a subscriber of Costco in Ontario, Canada just for fuel savings.
Here it is $0.12 to $0.15 cents more per liter for premium 91 vs their regular 87 - just depends on the day.
And yes, Shell here is a minimum of $0.40 per liter more per liter vs their regular 87, but I have seen it as high a difference of $0.55 per liter more expensive vs their regular 87.
Both have zero ethanol in their premium fuels, but is Shell V-Power 91 really that much better!?
My HEMI really doesn't notice too much a difference that I can discernably tell, but my **** dyno tells me that the Shell V-Power 91 is a better grade of premium.
So, the only time I currently venture to Shell, which is right around the corner from my local Costco, is either when the Costco lines are ridiculously long because my time and my sanity are worth the extra $5 a tankful, or, when I am travelling all over Ontario for work.
But then again, I have my lady's CAA card in my wallet and it saves my $0.03 per liter at Shell, so I'll take a discount anywhere I can get it, especially with a 32 gallon tank...