Toptiergas.com

"Why TOP TIER
The intention of the TOP TIER Detergent Gasoline standards is to create a winning situation for gasoline retailers, auto manufacturers and drivers. Currently, many gasoline retailers provide fuels with lower-quality additive packages that can build up deposits on fuel injectors and on intake valves. Others can build up deposits in combustion chambers and may lead to intake valve sticking. These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness."

QuikTrip
Chevron
Texaco
MFA Oil Co.
Conoco
Phillips 66
76
Entec Stations
Shell
The Somerset Refinery, Inc.
Kwik Trip / Kwik Star
Aloha Petroleum
Tri-Par Oil Co.
Turkey Hill Minit Markets
Mileage Stations
Chevron Canada
Shell Canada
Petro-Canada
Sunoco Canada


Top Tier According to GM.com


  • Chevron
  • QuikTrip
  • ConocoPhillips (Conoco, Phillips 66, and 76 brands)
  • Shell
  • Entec Stations
  • MFA Oil Company (Break Time stores)
  • Kwik Trip, Inc. (Kwik Trip / Kwik Star)
  • The Somerset Refinery, Inc. (Somerset Oil)
  • Aloha Petroleum (Aloha Petroleum, Jiffy Mart, and Mahalo brands)
  • Tri-Par Oil Co.
Automotive.com

"Shell regular and Plus gasolines, which meet the "Top Tier" standard, also contain more than two times the amount of cleaning agents required by the EPA. Shell V-Power goes even further -- it has more than five times the minimum amount of cleaning agents required by government standards and twice the cleaning agents required by the "Top Tier" standard. While the "Top Tier" standard is designed to protect engines from the future build-up of carbon deposits, Shell V-Power is specifically formulated to actively clean your engine as you drive giving it the ability to clean-up deposits that have already built up on intake valves and fuel injectors."