There is conflicting anecdotal evidence regarding whether Costco gas burns faster than other brands. Some users claim to experience a slight decrease in mileage with Costco gas, reporting 3-4 miles less per gallon compared to other fuels [2]. On the contrary, others argue that Costco gas provides good mileage without causing any harm to the engine [6].
Ultimately, the impact on fuel efficiency may vary from person to person and vehicle to vehicle. It’s advisable to consider individual experiences and conduct personal observations to determine if Costco gas affects your car’s mileage.
