[quote=equalizer]Costco is not top tier gas member. Mostly marketing, but there is some testing. BTW, M5 fans don’t seem to use Costco. Only time I’m glad I’m not burdened by M5 ownership. I just use mobil 89 by the house, a little more than Costco but no long lines. 240K on one car and still going strong.
Will the Shell next to Costco lower prices??[/quote]
I think the top tier thing was more of a marketing scam a few years back, and since then I think costco has added added additives above the minimum standards for some time…
I’d be more worried how clean those gas tanks are and how often fuel is turned over in the station….
Fuel sold in CA i believe go through 2 terminals anyway, so I think any difference would be in the additives added thereafter….
Up to know I’ve been kinda of a Shell/Mobil/Chevron person, with slight costco fillups when I was there.
