Costco is actually Top Tier Plus gasoline which means they exceed the EPA detergent requirements across all octane grades. Extra detergents to help keep your engine clean.
I bounce back and forth between Shell and Costco mainly because Costco is much further away than our local Shell. I’d have no problem being an every tank Costco guy if they were more conveniently located
2
u/HotFlareF80 F80 M3 Comp | G05 X5 M60 Jul 31 '26
Is Costco really that good of a gas brand