Top Tier gas: is premium-brand fuel actually better?

"Top Tier" isn't about octane — it's a detergent standard. Top Tier gasoline carries more cleaning additives than the EPA's minimum, which helps keep fuel injectors and intake valves clean over time.

What it does (and doesn't)

Independent testing has shown Top Tier fuels leave fewer engine deposits than minimum-additive gas, and several automakers recommend it. It does not add power or change whether your car needs premium octane — a regular-gas car still takes regular. This is about cleanliness, not octane.

Which brands are Top Tier

The standard is licensed, and the current list of Top Tier retailers (Chevron, Shell, Costco, Exxon, Mobil, QuikTrip, Phillips 66 and many more) is published at toptiergas.com. Membership changes, so check the official list rather than assuming a brand qualifies.

Bottom line: Top Tier is a real but modest long-term benefit for engine cleanliness — not a miracle, and not the same thing as premium octane.

Top Tier is an industry detergent standard; retailer list per toptiergas.com.